Inactivation of Bmp4 from the Tbx1 Expression Domain Causes Abnormal Pharyngeal Arch Artery and Cardiac Outflow Tract Remodeling

PubMed Central

Nie, Xuguang; Brown, Christopher B.; Wang, Qin; Jiao, Kai

2011-01-01

Maldevelopment of outflow tract and aortic arch arteries is among the most common forms of human congenital heart diseases. Both Bmp4 and Tbx1 are known to play critical roles during cardiovascular development. Expression of these two genes partially overlaps in pharyngeal arch areas in mouse embryos. In this study, we applied a conditional gene inactivation approach to test the hypothesis that Bmp4 expressed from the Tbx1 expression domain plays a critical role for normal development of outflow tract and pharyngeal arch arteries. We showed that inactivation of Bmp4 from Tbx1-expressing cells leads to the spectrum of deformities resembling the cardiovascular defects observed in human DiGeorge syndrome patients. Inactivation of Bmp4 from the Tbx1 expression domain did not cause patterning defects, but affected remodeling of outflow tract and pharyngeal arch arteries. Our further examination revealed that Bmp4 is required for normal recruitment/differentiation of smooth muscle cells surrounding the PAA4 and survival of outflow tract cushion mesenchymal cells. PMID:21123999

Aortic Arch Pulse Wave Velocity Assessed by Magnetic Resonance Imaging as a Predictor of Incident Cardiovascular Events: The MESA (Multi-Ethnic Study of Atherosclerosis).

PubMed

Ohyama, Yoshiaki; Ambale-Venkatesh, Bharath; Noda, Chikara; Kim, Jang-Young; Tanami, Yutaka; Teixido-Tura, Gisela; Chugh, Atul R; Redheuil, Alban; Liu, Chia-Ying; Wu, Colin O; Hundley, W Gregory; Bluemke, David A; Guallar, Eliseo; Lima, Joao A C

2017-09-01

The predictive value of aortic arch pulse wave velocity (PWV) assessed by magnetic resonance imaging for cardiovascular disease (CVD) events has not been fully established. The aim of the present study was to evaluate the association of arch PWV with incident CVD events in MESA (Multi-Ethnic Study of Atherosclerosis). Aortic arch PWV was measured using magnetic resonance imaging at baseline in 3527 MESA participants (mean age, 62±10 years at baseline; 47% men) free of overt CVD. Cox regression was used to evaluate the risk of incident CVD (coronary heart disease, stroke, transient ischemic attack, or heart failure) in relation to arch PWV adjusted for age, sex, race, and CVD risk factors. The median value of arch PWV was 7.4 m/s (interquartile range, 5.6-10.2). There was significant interaction between arch PWV and age for outcomes, so analysis was stratified by age categories (45-54 and >54 years). There were 456 CVD events during the 10-year follow-up. Forty-five to 54-year-old participants had significant association of arch PWV with incident CVD independent of CVD risk factors (hazard ratio, 1.44; 95% confidence interval, 1.07-1.95; P =0.018; per 1-SD increase for logarithmically transformed PWV), whereas >54-year group did not ( P =0.93). Aortic arch PWV assessed by magnetic resonance imaging is a significant predictor of CVD events among middle-aged (45-54 years old) individuals, whereas arch PWV is not associated with CVD among an elderly in a large multiethnic population. © 2017 American Heart Association, Inc.

The evolution of amphibian metamorphosis: insights based on the transformation of the aortic arches of Pelobates fuscus (Anura)

PubMed Central

Kolesová, Hana; Lametschwandtner, Alois; Roček, Zbyněk

2007-01-01

In order to gain insights into how the aortic arches changed during the transition of vertebrates to land, transformations of the aortic arches during the metamorphosis of Pelobates fuscus were investigated and compared with data from the early development of a recent ganoid fish Amia calva and a primitive caudate amphibian Salamandrella keyserlingi. Although in larval Pelobates, as in other non-pipid anurans, the gill arches serve partly as a filter-feeding device, their aortic arches maintain the original piscine-like arrangement, except for the mandibular and hyoid aortic arches which were lost. As important pre-adaptations for breathing of atmospheric oxygen occur in larval Pelobates (which have well-developed, though non-respiratory lungs and pulmonary artery), transformation of aortic arches during metamorphosis is fast. The transformation involves disappearance of the ductus Botalli, which results in a complete shunting of blood into the lungs and skin, disappearance of the ductus caroticus, which results in shunting of blood into the head through the arteria carotis interna, and disappearance of arch V, which results in shunting blood to the body through arch IV (systemic arch). It is supposed that the branching pattern of the aortic arches of permanently water-dwelling piscine ancestors, of intermediate forms which occasionally left the water and of primitive tetrapods capable of spending longer periods of time on land had been the same as in the prematamorphic anuran larvae or in some metamorphosed caudates in which the ductus caroticus and ductus Botalli were not interrupted, and arch V was still complete. PMID:17367494

The evolution of amphibian metamorphosis: insights based on the transformation of the aortic arches of Pelobates fuscus (Anura).

PubMed

Kolesová, Hana; Lametschwandtner, Alois; Rocek, Zbynek

2007-04-01

In order to gain insights into how the aortic arches changed during the transition of vertebrates to land, transformations of the aortic arches during the metamorphosis of Pelobates fuscus were investigated and compared with data from the early development of a recent ganoid fish Amia calva and a primitive caudate amphibian Salamandrella keyserlingi. Although in larval Pelobates, as in other non-pipid anurans, the gill arches serve partly as a filter-feeding device, their aortic arches maintain the original piscine-like arrangement, except for the mandibular and hyoid aortic arches which were lost. As important pre-adaptations for breathing of atmospheric oxygen occur in larval Pelobates (which have well-developed, though non-respiratory lungs and pulmonary artery), transformation of aortic arches during metamorphosis is fast. The transformation involves disappearance of the ductus Botalli, which results in a complete shunting of blood into the lungs and skin, disappearance of the ductus caroticus, which results in shunting of blood into the head through the arteria carotis interna, and disappearance of arch V, which results in shunting blood to the body through arch IV (systemic arch). It is supposed that the branching pattern of the aortic arches of permanently water-dwelling piscine ancestors, of intermediate forms which occasionally left the water and of primitive tetrapods capable of spending longer periods of time on land had been the same as in the prematamorphic anuran larvae or in some metamorphosed caudates in which the ductus caroticus and ductus Botalli were not interrupted, and arch V was still complete.

Neural crest contribution to the cardiovascular system.

PubMed

Brown, Christopher B; Baldwin, H Scott

2006-01-01

Normal cardiovascular development requires complex remodeling of the outflow tract and pharyngeal arch arteries to create the separate pulmonic and systemic circulations. During remodeling, the outflow tract is septated to form the ascending aorta and the pulmonary trunk. The initially symmetrical pharyngeal arch arteries are remodeled to form the aortic arch, subclavian and carotid arteries. Remodeling is mediated by a population of neural crest cells arising between the mid-otic placode and somite four called the cardiac neural crest. Cardiac neural crest cells form smooth muscle and pericytes in the great arteries, and the neurons of cardiac innervation. In addition to the physical contribution of smooth muscle to the cardiovascular system, cardiac neural crest cells also provide signals required for the maintenance and differentiation of the other cell layers in the pharyngeal apparatus. Reciprocal signaling between the cardiac neural crest cells and cardiogenic mesoderm of the secondary heart field is required for elaboration of the conotruncus and disruption in this signaling results in primary myocardial dysfunction. Cardiovascular defects attributed to the cardiac neural crest cells may reflect either cell autonomous defects in the neural crest or defects in signaling between the neural crest and adjacent cell layers.

Canadian Cardiovascular Society/Canadian Society of Cardiac Surgeons/Canadian Society for Vascular Surgery Joint Position Statement on Open and Endovascular Surgery for Thoracic Aortic Disease.

PubMed

Appoo, Jehangir J; Bozinovski, John; Chu, Michael W A; El-Hamamsy, Ismail; Forbes, Thomas L; Moon, Michael; Ouzounian, Maral; Peterson, Mark D; Tittley, Jacques; Boodhwani, Munir

2016-06-01

In 2014, the Canadian Cardiovascular Society (CCS) published a position statement on the management of thoracic aortic disease addressing size thresholds for surgery, imaging modalities, medical therapy, and genetics. It did not address issues related to surgical intervention. This joint Position Statement on behalf of the CCS, Canadian Society of Cardiac Surgeons, and the Canadian Society for Vascular Surgery provides recommendations about thoracic aortic disease interventions, including: aortic valve repair, perfusion strategies for arch repair, extended arch hybrid reconstruction for acute type A dissection, endovascular management of arch and descending aortic aneurysms, and type B dissection. The position statement is constructed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and has been approved by the primary panel, an international secondary panel, and the CCS Guidelines Committee. Advent of endovascular technology has improved aortic surgery safety and extended the indications of minimally invasive thoracic aortic surgery. The combination of safer open surgery with endovascular treatment has improved patient outcomes in this rapidly evolving subspecialty field of cardiovascular surgery. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Double Aortic Arch With Previously Undescribed Head and Neck Vessel Branching.

PubMed

Hashemi, Sassan; Parks, W James; Sallee, Denver; Slesnick, Timothy

2017-04-01

Vascular ring in the form of a double aortic arch is a rare anomaly that can cause airway compression. It occasionally occurs with unusual head and neck vessel branching. A 5-year-old boy with chronic respiratory symptoms was referred because of a tracheal indentation on his chest x-ray. Magnetic resonance imaging showed a double aortic arch with arch origins of a common carotid, vertebral, and subclavian on the right and internal and external carotids, vertebral, and subclavian arteries on the left. Our case represents, to our knowledge, the first report of a double aortic arch with 7 separate vessels arising from the transverse arches. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Simulation-based power calculation for designing interrupted time series analyses of health policy interventions.

PubMed

Zhang, Fang; Wagner, Anita K; Ross-Degnan, Dennis

2011-11-01

Interrupted time series is a strong quasi-experimental research design to evaluate the impacts of health policy interventions. Using simulation methods, we estimated the power requirements for interrupted time series studies under various scenarios. Simulations were conducted to estimate the power of segmented autoregressive (AR) error models when autocorrelation ranged from -0.9 to 0.9 and effect size was 0.5, 1.0, and 2.0, investigating balanced and unbalanced numbers of time periods before and after an intervention. Simple scenarios of autoregressive conditional heteroskedasticity (ARCH) models were also explored. For AR models, power increased when sample size or effect size increased, and tended to decrease when autocorrelation increased. Compared with a balanced number of study periods before and after an intervention, designs with unbalanced numbers of periods had less power, although that was not the case for ARCH models. The power to detect effect size 1.0 appeared to be reasonable for many practical applications with a moderate or large number of time points in the study equally divided around the intervention. Investigators should be cautious when the expected effect size is small or the number of time points is small. We recommend conducting various simulations before investigation. Copyright © 2011 Elsevier Inc. All rights reserved.

Secondary hypertension due to isolated interrupted aortic arch in a 45-year-old person: A case report.

PubMed

Zhou, Jian Mei; Liu, Xin Wen; Yang, Yi; Wang, Bo Zhong; Wang, Jian An

2017-12-01

Though it is rare, isolated interrupted aortic arch (IAA) could lead to hypertension. Surgical repair is the only effective curative method to treat IAA conditions and patients with IAA can hardly survive to adulthood with medication alone. We report an IAA case that of a 45-year-old male patient who survived for 45 years without surgical treatment. A 45-year-old man was referred to the hospital presenting with abnormal blood pressure level. Both computed tomography angiogram (CTA) and angiography revealed IAA. The patient was diagnosed as IAA based on computed tomography angiogram (CTA) and angiography. The patient's blood pressure was severely high and refractory. He refused surgical treatment and accepted antihypertensive medication for 10 days. The patient's office blood pressure level was abnormal, fluctuating between 140/90 and 160/100 mm Hg, but 24-hour ambulatory blood pressure monitoring showed normal level. Hypertension due to IAA could be controlled with medications, even surgery is not performed. The discrepancy between ambulatory and office blood pressure levels may be due to the white coat effect.

Fgf8 expression in the Tbx1 domain causes skeletal abnormalities and modifies the aortic arch but not the outflow tract phenotype of Tbx1 mutants

PubMed Central

Vitelli, Francesca; Zhang, Zhen; Huynh, Tuong; Sobotka, Angela; Mupo, Annalisa; Baldini, Antonio

2007-01-01

Fgf8 and Tbx1 have been shown to interact in patterning the aortic arch, and both genes are required in formation and growth of the outflow tract of the heart. However, the nature of the interaction of the two genes is unclear. We have utilized a novel Tbx1Fgf8 allele which drives Fgf8 expression in Tbx1-positive cells and an inducible Cre-LoxP recombination system to address the role of Fgf8 in Tbx1 positive cells in modulating cardiovascular development. Results support a requirement of Fgf8 in Tbx1 expressing cells to finely control patterning of the aortic arch and great arteries specifically during the pharyngeal arch artery remodeling process and indicate that the endoderm is the most likely site of this interaction. Furthermore, our data suggest that Fgf8 and Tbx1 play independent roles in regulating outflow tract development. This finding is clinically relevant since TBX1 is the candidate for DGS/VCFS, characterized clinically by variable expressivity and reduced penetrance of cardiovascular defects; Fgf8 gene variants may provide molecular clues to this variability. PMID:16696966

Non-Invasive Methods of Cardiovascular Exploration in Aerospace Medicine.

DTIC Science & Technology

1983-12-01

inferior vena cava Aorta right atrium filling chamber of right ventricle. Trunk of pulmonary art cry Posterior border: almost vertical AP lower arch left ... left ventricle. Inferior Vena cava infundihbulum L Upper border aortic arch Lower border superimposed borders of the RV LV right and left ventricles...iliac aneurisms is possible. isotopic phlebography is useful in the investigation of the permeability of the inferior vena cava

Assessment of aortic stiffness in patients with ankylosing spondylitis using cardiovascular magnetic resonance.

PubMed

Biesbroek, P Stefan; Heslinga, Sjoerd C; van de Ven, Peter M; Peters, Mike J L; Amier, Raquel P; Konings, Thelma C; Maroules, Christopher D; Ayers, Colby; Joshi, Parag H; van der Horst-Bruinsma, Irene E; van Halm, Vokko P; van Rossum, Albert C; Nurmohamed, Michael T; Nijveldt, Robin

2018-05-12

To evaluate aortic stiffness in patients with ankylosing spondylitis (AS) using cardiovascular magnetic resonance (CMR) and to assess its association with AS characteristics and left ventricular (LV) remodeling. In this prospective study, 14 consecutive AS patients were each matched to two controls without cardiovascular symptoms or known cardiovascular disease who underwent CMR imaging for the assessment of aortic arch pulse wave velocity (PWV) at 1.5 Tesla. To enhance comparability of the samples, matching was done with replacement resulting in 20 unique controls. Only AS patients with abnormal findings on screening echocardiography were included in this exploratory study. Cine CMR was used to assess LV geometry and systolic function, and late gadolinium enhancement was performed to determine the presence of myocardial hyperenhancement (i.e., fibrosis). Aortic arch PWV was significantly higher in the AS group compared with the control group (median 9.7 m/s, interquartile range [IQR] 7.1 to 11.8 vs. 6.1 m/s, IQR 4.6 to 7.6 m/s; p < 0.001). PWV was positively associated with functional disability as measured by BASFI (R: 0.62; p = 0.018). Three patients (21%) with a non-ischemic pattern of hyperenhancement showed increased PWV (11.7, 12.3, and 16.5 m/s) as compared to the 11 patients without hyperenhancement (9.0 m/s, IQR 6.6 to 10.5 m/s; p = 0.022). PWV was inversely associated with LV ejection fraction (R: - 0.63; p = 0.015), but was not found to be statistically correlated to LV volumes or mass. Aortic arch PWV was increased in our cohort of patients with AS. Higher PWV in the aortic arch was associated with functional disability, the presence of non-ischemic hyperenhancement, and reduced LV systolic function.

Contemporary results of surgical repair of recurrent aortic arch obstruction.

PubMed

Mery, Carlos M; Khan, Muhammad S; Guzmán-Pruneda, Francisco A; Verm, Raymond; Umakanthan, Ramanan; Watrin, Carmen H; Adachi, Iki; Heinle, Jeffrey S; McKenzie, E Dean; Fraser, Charles D

2014-07-01

There is a paucity of data on the current outcomes of surgical intervention for recurrent aortic arch obstruction (RAAO) after initial aortic arch repair in children. The goal of this study is to report the long-term results in these patients. All patients undergoing surgical intervention for RAAO at Texas Children's Hospital from 1995 to 2012 were included. The cohort was divided into four groups based on initial procedure: (1) simple coarctation repair, (2) Norwood procedure, (3) complex congenital heart disease, and (4) interrupted aortic arch. A total of 48 patients age 9 months (range, 22 days to 36 years) underwent 49 procedures for RAAO. All patients had an anatomic repair consisting of either patch aortoplasty (n=27, 55%), aortic arch advancement (n=8, 16%), sliding arch aortoplasty (n=6, 12%), placement of an interposition graft (n=2, 17%), reconstruction with donor allograft (n=4, 8%), extended end-to-end anastomosis (n=1, 2%), or redo Norwood-type reconstruction (n=1, 2%). Most procedures (n=46, 94%) were performed through a median sternotomy using cardiopulmonary bypass. At a median follow-up of 6.1 years (range, 9 days to 17 years), only 2 patients required surgical or catheter-based intervention for RAAO. Hypertension was present in 10% of patients at last follow-up. There were no neurologic or renal complications. There was 1 perioperative death after an aortic arch advancement in group 1. Four other patients have died during follow-up, none of the deaths related to RAAO. Anatomic repair of RAAO is a safe procedure associated with low morbidity and mortality, and low long-term reintervention rates. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Selective cerebro-myocardial perfusion in complex congenital aortic arch pathology: a novel technique.

PubMed

De Rita, Fabrizio; Lucchese, Gianluca; Barozzi, Luca; Menon, Tiziano; Faggian, Giuseppe; Mazzucco, Alessandro; Luciani, Giovanni Battista

2011-11-01

Simultaneous cerebro-myocardial perfusion has been described in neonatal and infant arch surgery, suggesting a reduction in cardiac morbidity. Here reported is a novel technique for selective cerebral perfusion combined with controlled and independent myocardial perfusion during surgery for complex or recurrent aortic arch lesions. From April 2008 to April 2011, 10 patients with arch pathology underwent surgery (two hypoplastic left heart syndrome [HLHS], four recurrent arch obstruction, two aortic arch hypoplasia + ventricular septal defect [VSD], one single ventricle + transposition of the great arteries + arch hypoplasia, one interrupted aortic arch type B + VSD). Median age was 63 days (6 days-36 years) and median weight 4.0 kg (1.6-52). Via midline sternotomy, an arterial cannula (6 or 8 Fr for infants) was directly inserted into the innominate artery or through a polytetrafluoroethylene (PTFE) graft (for neonates <2.0 kg). A cardioplegia delivery system was inserted into the aortic root. Under moderate hypothermia, ascending and descending aorta were cross-clamped, and "beating heart and brain" aortic arch repair was performed. Arch repair was composed of patch augmentation in five, end-to-side anastomosis in three, and replacement in two patients. Average cardiopulmonary bypass time was 163 ± 68 min (71-310). In two patients only (one HLHS, one complex single ventricle), a period of cardiac arrest was required to complete intracardiac repair. In such cases, antegrade blood cardioplegia was delivered directly via the same catheter used for selective myocardial perfusion. Average time of splanchnic ischemia during cerebro-myocardial perfusion was 39 ± 18 min (17-69). Weaning from cardiopulmonary bypass was achieved without inotropic support in three and with low dose in seven patients. One patient required veno-arterial extracorporeal membrane oxygenation. Four patients, body weight <3.0 kg, needed delayed sternal closure. No neurologic dysfunction was noted. Renal function proved satisfactory in all, while liver function was adequate in all but one. The present experience suggests that selective and independent cerebro-myocardial perfusion is feasible in patients with complex or recurrent aortic arch disease, starting from premature newborn less than 2.0 kg of body weight to adults. The technique is as safe as previously reported methods of cerebro-myocardial perfusion and possibly more versatile. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Increased soluble vascular cell adhesion molecule-1 plasma levels and soluble intercellular adhesion molecule-1 during antiretroviral therapy interruption and retention of elevated soluble vascular cellular adhesion molecule-1 levels following resumption of antiretroviral therapy.

PubMed

Papasavvas, Emmanouil; Azzoni, Livio; Pistilli, Maxwell; Hancock, Aidan; Reynolds, Griffin; Gallo, Cecile; Ondercin, Joe; Kostman, Jay R; Mounzer, Karam; Shull, Jane; Montaner, Luis J

2008-06-19

We investigated the effect of short viremic episodes on soluble markers associated with endothelial stress and cardiovascular disease risk in chronically HIV-1-infected patients followed during continuous antiretroviral therapy, antiretroviral therapy interruption and antiretroviral therapy resumption. We assessed changes in plasma levels of von Willebrand factor, soluble vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 by enzyme-linked immunosorbent assay, as well as T-cell activation (CD8+/CD38+, CD8+/HLA-DR+ and CD3+/CD95+) by flow cytometry, in 36 chronically HIV-1-infected patients participating in a randomized study. Patients were divided into the following three groups: a, on continuous antiretroviral therapy; b, on a 6-week antiretroviral therapy interruption; or c, on antiretroviral therapy interruption extended to the achievement of viral set point. Although all measurements remained stable over a 40-week follow-up on antiretroviral therapy, plasma levels of soluble vascular cell adhesion molecule-1 (P < 0.0001) and soluble intercellular adhesion molecule-1 (P = 0.003) increased during treatment interruption in correlation with viral rebound and T-cell activation. No significant changes in von Willebrand factor were observed in any of the groups. After resuming antiretroviral therapy, soluble vascular cell adhesion molecule-1 levels remained elevated even after achievement of viral suppression to less than 50 copies/ml. The prompt rise in plasma soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-1 upon viral rebound suggests an acute increase in endothelial stress upon treatment interruption, which may persists after viral resuppression of virus. Thus, viral replication during short-term treatment interruption may increase the overall cardiovascular risk during and beyond treatment interruption.

Growth of left ventricular outflow tract and predictors of future re-intervention after repair for ventricular septal defect and aortic arch obstruction.

PubMed

Jijeh, Abdulraouf; Ismail, Muna; Alhabshan, Fahad

2017-09-01

Ventricular septal defect and aortic arch obstruction are usually associated with a narrow left ventricular outflow tract. The aim of the present study was to analyse the growth and predictors of future obstruction of the left ventricular outflow tract after surgical repair. We carried out a retrospective review of patients who underwent repair for ventricular septal defect and aortic arch obstruction - coarctation or interrupted aortic arch - between July, 2002 and June, 2013. Echocardiographic data were reviewed, and the need for re-intervention was evaluated. A total of 89 patients were included in this study. A significant left ventricular outflow tract growth was noticed after surgical repair. Preoperatively, the mean left ventricular outflow tract Z-score was -1.46±1 (range -5.5 to 1.1) and increased to a mean value of -0.7±1.3 (range -2.7 to 3.2) at last follow-up (p=0.0001), demonstrating relevant growth of the left ventricular outflow tract after repair for ventricular septal defect and aortic arch obstruction. After primary repair, 11 patients (12.3%) required re-intervention with surgical repair for left ventricular outflow tract obstruction after a mean period of 36±21 months. There were no significant differences in age, weight, and indexed aortic valve and left ventricular outflow tract measurements between those who developed obstruction and those who did not. Significant left ventricular outflow tract growth is expected after repair of ventricular septal defect and aortic arch obstruction. Small aortic valve and left ventricular outflow tract at diagnosis are not risk factors to predict the need for surgical re-intervention for left ventricular outflow tract obstruction in future.

Acute effects of aircraft noise on cardiovascular admissions - an interrupted time-series analysis of a six-day closure of London Heathrow Airport caused by volcanic ash.

PubMed

Pearson, Tim; Campbell, Michael J; Maheswaran, Ravi

2016-08-01

Acute noise exposure may acutely increase blood pressure but the hypothesis that acute exposure to aircraft noise may trigger cardiovascular events has not been investigated. This study took advantage of a six-day closure of a major airport in April 2010 caused by volcanic ash to examine if there was a decrease in emergency cardiovascular hospital admissions during or immediately after the closure period, using an interrupted daily time-series study design. The population living within the 55dB(A) noise contour was substantial at 0.7 million. The average daily admission count was 13.9 (SD 4.4). After adjustment for covariates, there was no evidence of a decreased risk of hospital admission from cardiovascular disease during the closure period (relative risk 0.97 (95% CI 0.75-1.26)). Using lags of 1-7 days gave similar results. Further studies are needed to investigate if transient aircraft noise exposure can trigger acute cardiovascular events. Copyright © 2016. Published by Elsevier Ltd.

How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

PubMed Central

Habertheuer, Andreas; Wiedemann, Dominik; Kocher, Alfred; Laufer, Guenther; Vallabhajosyula, Prashanth

2015-01-01

Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA) or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data. PMID:26713319

Aortic arch syndrome

MedlinePlus

... including: Congenital absence of a branch of the aorta Isolation of the subclavian arteries Vascular rings An ... Braverman AC. Diseases of the aorta. In: Bonow RO, Mann DL, Zipes DP, ... Heart Disease: A Textbook of Cardiovascular Medicine . 10th ...

Prevalence of Coronal Pulp Stones and Its Relation with Systemic Disorders in Northern Indian Central Punjabi Population

PubMed Central

Bains, Sandeep Kumar; Bhatia, Archana; Singh, Harkanwal Preet; Biswal, Swati Swagatika; Kanth, Shashi; Nalla, Srinivas

2014-01-01

Aim. To estimate the prevalence of coronal pulp stones in the molar teeth of dental outpatients of Sunam, Sangrur district, Punjab, India, to report any association between occurrence of pulp stones with age, gender, dental arch, side, and dental status and to find out correlation between pulp stones with dental and systemic diseases. Materials and Methods. 500 routine dental outpatients within age group of 18–67 years were involved in the study. Molar bitewing of left and right side of each patient was taken with XCP bitewing instrument and size 2 film. The presence or absence of pulp stones was recorded. Chi-square analysis was used to record the prevalence of pulp stones and to compare it with demographic and systemic factors. Results. Overall prevalence of pulp stones was 41.8%. Pulp stones were significantly higher in maxilla (11.59%) than mandible (6.54%), left side than right side, and first molar than other molars. Higher numbers of pulp stones were recorded in patients with cardiovascular disease (38.89%) than with cholelithiasis and renal lithiasis. Conclusion. Pulp stones were higher in maxillary arch than mandibular arch and in females than males. Cardiovascular patients had higher number of pulp stones than other groups. PMID:24944821

Trap Model for Clogging and Unclogging in Granular Hopper Flows.

PubMed

Nicolas, Alexandre; Garcimartín, Ángel; Zuriguel, Iker

2018-05-11

Granular flows through narrow outlets may be interrupted by the formation of arches or vaults that clog the exit. These clogs may be destroyed by vibrations. A feature which remains elusive is the broad distribution p(τ) of clog lifetimes τ measured under constant vibrations. Here, we propose a simple model for arch breaking, in which the vibrations are formally equivalent to thermal fluctuations in a Langevin equation; the rupture of an arch corresponds to the escape from an energy trap. We infer the distribution of trap depths from experiments made in two-dimensional hoppers. Using this distribution, we show that the model captures the empirically observed heavy tails in p(τ). These heavy tails flatten at large τ, consistently with experimental observations under weak vibrations. But, here, we find that this flattening is systematic, which casts doubt on the ability of gentle vibrations to restore a finite outflow forever. The trap model also replicates recent results on the effect of increasing gravity on the statistics of clog formation in a static silo. Therefore, the proposed framework points to a common physical underpinning to the processes of clogging and unclogging, despite their different statistics.

Trap Model for Clogging and Unclogging in Granular Hopper Flows

NASA Astrophysics Data System (ADS)

Nicolas, Alexandre; Garcimartín, Ángel; Zuriguel, Iker

2018-05-01

Granular flows through narrow outlets may be interrupted by the formation of arches or vaults that clog the exit. These clogs may be destroyed by vibrations. A feature which remains elusive is the broad distribution p (τ ) of clog lifetimes τ measured under constant vibrations. Here, we propose a simple model for arch breaking, in which the vibrations are formally equivalent to thermal fluctuations in a Langevin equation; the rupture of an arch corresponds to the escape from an energy trap. We infer the distribution of trap depths from experiments made in two-dimensional hoppers. Using this distribution, we show that the model captures the empirically observed heavy tails in p (τ ). These heavy tails flatten at large τ , consistently with experimental observations under weak vibrations. But, here, we find that this flattening is systematic, which casts doubt on the ability of gentle vibrations to restore a finite outflow forever. The trap model also replicates recent results on the effect of increasing gravity on the statistics of clog formation in a static silo. Therefore, the proposed framework points to a common physical underpinning to the processes of clogging and unclogging, despite their different statistics.

Outcomes of aortopulmonary window repair in children: 33 years of experience.

PubMed

Naimo, Phillip S; Yong, Matthew S; d'Udekem, Yves; Brizard, Christian P; Kelly, Andrew; Weintraub, Robert; Konstantinov, Igor E

2014-11-01

The purpose of this study was to assess the outcomes of children undergoing repair of aortopulmonary window (APW). We conducted a retrospective review of all children (n=43) who underwent surgical repair of APW between 1980 and 2013. Median age at surgery was 40 days (range, 13 to 125). Simple APW was present in 15 of 43 patients (35%), and 28 of 43 patients (65%) patients had concomitant cardiovascular anomalies. The aorta was repaired by direct suturing in 36 patients (84%) patients and patching in 7 patients (16%). The main pulmonary artery was repaired by direct suturing in 22 patients (51%) patients and by patching in 21 (49%). Cardiopulmonary bypass was used in 42 of the 43 patients (97.7%). Single-staged repair of concomitant cardiovascular anomalies was undertaken in 26 of 28 patients (93%). Only 2 of the 28 patients (7%) underwent repair of interrupted aortic arch before APW repair. Operative mortality was 6.7% (1 of 15 patients) among patients with simple APW and 18% (5 of 28 patients) among patients with concomitant anomalies. Operative weight less than 2.5 kg was associated with mortality on univariable analysis (p=0.02). Median follow-up was 10.1 years (range, 0.17 to 24.2). There were no late deaths. Overall survival was 86% (95% confidence interval: 71.3 to 94.2) at 10 years. Freedom from reoperation was 95.3% (95% confidence interval: 86.2 to 99.9) at 10 years. At last follow-up, all patients were in New York Heart Association functional class I/II. Survival beyond discharge from the hospital is associated with excellent outcomes. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Complete trisomy 9 with unusual phenotypic associations: Dandy-Walker malformation, cleft lip and cleft palate, cardiovascular abnormalities.

PubMed

Tonni, Gabriele; Lituania, Mario; Chitayat, David; Bonasoni, Maria Paola; Keating, Sarah; Thompson, Megan; Shannon, Patrick

2014-12-01

Trisomy 9 is a rare chromosomal abnormality usually associated with first-trimester miscarriage; few fetuses survive until the second trimester. We report two new cases of complete trisomy 9 that both present unusual phenotypic associations, and we analyze the genetic pathway involved in this chromosomal abnormality. The first fetus investigated showed Dandy-Walker malformation, cleft lip, and cleft palate) at the second trimester scan. Cardiovascular abnormalities were characterized by a right-sided, U-shaped aortic arch associated with a ventricular septal defect (VSD). Symmetrical intrauterine growth restriction and multicystic dysplastic kidney disease were associated findings. The second fetus showed a dysmorphic face, bilateral cleft lip, hypoplastic corpus callosum, and a Dandy-Walker malformation. Postmortem examination revealed cardiovascular abnormalities such as persistent left superior vena cava draining into the coronary sinus, membranous ventricular septal defect, overriding aorta, pulmonary valve with two cusps and three sinuses, and the origin of the left subclavian artery distal to the junction of ductus arteriosus and aortic arch. Complete trisomy 9 may result in a wide spectrum of congenital abnormalities, and the presented case series contributes further details on the phenotype of this rare aneuploidy. Copyright © 2014. Published by Elsevier B.V.

Loss of pulse pressure amplification between the ascending and descending aorta in patients after an aortic arch repair.

PubMed

Murakami, Tomoaki; Shiraishi, Masahiro; Nawa, Tomohiro; Takeda, Atsuhito

2017-03-01

One of the most important problems in patients with an aortic coarctation after an aortic arch repair is future cardiovascular disease. We previously reported the enhancement of the aortic pressure wave reflection in patients and hypothesized that the enhancement was caused by a new pressure wave reflection generated from the repaired site. To prove the hypothesis, we analyzed the pressure waveform in the ascending and descending aorta and examined their pulse pressure (PP) amplification. Fifteen patients after an aortic arch repair without a recoarctation were enrolled. The ascending and descending aorta pressure waveforms were recorded by a pressure sensor mounted catheter. The pressures were compared with those of age-matched controls. The patient's age was 7.3 ± 2.7 years, and they underwent the aortic arch repair at 30.1 ± 29.0 days. The ascending aorta SBP (106.1 ± 12.7 mmHg) was higher than in the control patients (97.9 ± 14.3) (P = 0.015). The PP at the ascending aorta in the patients (41.3 ± 7.8) was wider than that in the controls (36.4 ± 5.0) (P = 0.010). There was no difference concerning the PP at the descending aorta between the patients (41.0 ± 7.7) and controls (40.5 ± 6.5). The difference in the PP between the descending and ascending aorta (PP at the descending aorta - PP at the ascending aorta) in the patients was -0.3 ± 1.7 and 5.1 ± 2.9 in the controls (P < 0.0001). The ascending aortic PP was augmented in the patients after the aortic arch repair. It could be one of the causes of future cardiovascular disease.

Prenatal Diagnosis of Fetal Interrupted Aortic Arch Type A by Two-Dimensional Echocardiography and Four-Dimensional Echocardiography with B-Flow Imaging and Spatiotemporal Image Correlation.

PubMed

Zhang, Dongyu; Zhang, Ying; Ren, Weidong; Sun, Feifei; Guo, Yajun; Sun, Wei; Wang, Yu; Huang, Liping; Cai, Ailu

2016-01-01

Fetal interrupted aortic arch (IAA) is a rare cardiac anomaly and its prenatal diagnosis is challenging. The purpose of our report is to evaluate the use of two-dimensional echocardiography (2DE) and 4D echocardiography with B-flow imaging and spatiotemporal image correlation (4D BF-STIC) in detecting IAA type A (IAA-A). Twenty-three cases of confirmed IAA-A identified by fetal echocardiography were involved in the study. The fetal echocardiography image data were reviewed to analyze the ratio of right ventricle to left ventricle (RV/LV) diameter, the ratio of main pulmonary artery to ascending aorta (MPA/AAO) diameter, and the correlation of RV/LV diameter ratio and size of ventricular septal defect (VSD). 4D BF-STIC was performed in 21 fetuses using the sagittal view (4D BF-STIC-sagittal) and the four-chamber view (4D BF-STIC-4CV) as initial planes of view. An additional 183 normal fetuses were also included in our study. RV/LV and MPA/AAO ratios were calculated and compared with that of IAA-A fetuses. Fetal 2DE, 4D BF-STIC-sagittal, and 4D BF-STIC-4CV were used to visualize the aortic arch and its associated neck vessels. Six subgroups were evaluated according to gestational age. Fetal 2DE, 4D BF-STIC-sagittal, and 4D BF-STIC-4CV made the correct prenatal diagnosis of IAA-A in 19/23 (82.6%), 14/21 (66.7%), and 19/21 (90.5%) of patients, respectively. A significantly enlarged MPA combined with symmetric ventricles was found in the IAA-A fetuses, while the size of the VSD was negatively correlated with RV/LV ratio. 4D BF-STIC-sagittal and 4D BF-STIC-4CV were better than traditional 2D ultrasound in detecting the aortic arch and neck vessels between 17 and 28 gestational weeks and 29 to 40 gestational weeks in normal fetuses. It is demonstrated that IAA-A could be diagnosed by traditional fetal echocardiography, while 4D technique could better display the anatomic structure and the spatial relationships of the great arteries. Use of volume reconstruction may promote its clinical usage and help prenatal diagnosis. © 2015, Wiley Periodicals, Inc.

Airflow obstruction, atherosclerosis and cardiovascular risk factors in the AGES Reykjavik study.

PubMed

Gudmundsson, Gunnar; Margretardottir, Olof Birna; Sigurdsson, Martin Ingi; Harris, Tamara B; Launer, Lenore J; Sigurdsson, Sigurdur; Olafsson, Orn; Aspelund, Thor; Gudnason, Vilmundur

2016-09-01

Airflow limitation, i.e. reduced forced expiratory volume in 1-s (FEV1), is associated with increased prevalence of atherosclerosis, however, causal mechanisms remain elusive. The objective of the study was to determine if the association between airflow obstruction and markers of atherosclerosis is mediated by systemic inflammation. 1154 subjects from the longitudinal AGES Reykjavik study were included. Population characteristics, systemic inflammation markers from blood (white blood cell counts (WBC) and level of C-reactive protein (CRP)) were compared between patients with and without airflow limitation defined by reduced FEV1 on spirometry. Atherosclerosis burden was quantified by measurements of coronary artery calcium, aortic arch and distal aortic calcification in addition to carotid intimal media thickness (CIMT). Subjects were split into four groups according to smoking status and whether airflow limitation was present. There was a higher overall burden of atherosclerosis in ever-smokers compared to never-smokers, and in individuals with airflow obstruction compared to individuals without airflow obstruction. After adjusting for population characteristics, Framingham cardiovascular risk factors and markers of systemic inflammation (WBC and CRP), there was a significantly increased aortic arch and distal aorta calcification and higher CIMT measurement in individuals with airflow obstruction compared to individuals without airflow obstruction. After adjusting for population characteristics, Framingham cardiovascular risk factors and markers of systemic inflammation (WBC and CRP), there was a significantly increased aortic arch and distal aorta calcification and higher CIMT measurement in individuals with airflow obstruction compared to individuals without airflow obstruction. Systemic inflammation (WBC and CRP) does not appear to mediate the association between airflow limitation and atherosclerosis. Only airflow limitation and not systemic inflammation (WBC and CRP) appears to be an independent predictor of atherosclerosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Cardiovascular hoarseness: an unusual presentation to otolaryngologists.

PubMed

Fennessy, B G; Sheahan, P; McShane, D

2008-03-01

We discuss the case of a 73-year-old woman with a six-month history of hoarseness secondary to an aortic arch pseudoaneurysm. We present the findings of an extensive review of the literature relating to cardiovascular disorders involving the recurrent laryngeal nerve (i.e. Ortner's syndrome). Ortner's syndrome, also known as cardiovocal syndrome, is a rare condition, with few reports in the literature. This is only the second documented case of Ortner's syndrome in Great Britain and Ireland, and the first demonstrating an aortic pseudoaneurysm.

Contemporary patterns of surgery and outcomes for aortic coarctation: An analysis of the Society of Thoracic Surgeons Congenital Heart Surgery Database

PubMed Central

Ungerleider, Ross M.; Pasquali, Sara K.; Welke, Karl F.; Wallace, Amelia S.; Ootaki, Yoshio; Quartermain, Michael D.; Williams, Derek A.; Jacobs, Jeffrey P.

2013-01-01

Objective The objective of this study was to describe characteristics and early outcomes across a large multicenter cohort undergoing coarctation or hypoplastic aortic arch repair. Methods Patients undergoing coarctation or hypoplastic aortic arch repair (2006–2010) as their first cardiovascular operation in the Society of Thoracic Surgeons Congenital Heart Surgery Database were included. Group 1 patients consisted of those with coarctation or hypoplastic aortic arch without ventricular septal defect (coarctation or hypoplastic aortic arch, isolated); group 2, coarctation or hypoplastic aortic arch with ventricular septal defect (coarctation or hypoplastic aortic arch, ventricular septal defect); and group 3, coarctation or hypoplastic aortic arch with other major cardiac diagnoses (coarctation or hypoplastic aortic arch, other). Results The cohort included 5025 patients (95 centers): group 1, 2705 (54%); group 2, 840 (17%); and group 3, 1480 (29%). Group 1 underwent coarctation or hypoplastic aortic arch repair at an older age than groups 2 and 3 (groups 1, 2, and 3, 75%, 99%, and 88% < 1 year old, respectively; P<.0001). The most common operative techniques for coarctation or hypoplastic aortic arch repair (group 1) were end-to-end (33%) or extended end-to-end (56%) anastomosis. Overall mortality was 2.4%, and was 1%, 2.5%, and 4.8% for groups 1, 2, and 3 respectively (P < .0001). Ventricular septal defect management strategies for group 2 patients included ventricular septal defect closure (n = 211, 25%), pulmonary artery band (n = 89, 11%), or no intervention (n = 540, 64%) without significant difference in mortality (4%, 1%, 2%; P = .15). Postoperative complications occurred in 36% of patients overall and were more common in groups 2 and 3. There were no occurrences of spinal cord injury (0/973). Conclusions In the current era, primary coarctation or hypoplastic aortic arch repair is performed predominantly in neonates and infants. Overall mortality is low, although those with concomitant defects are at risk for higher morbidity and mortality. The risk of spinal cord injury is lower than previously reported. PMID:23098750

Anterior spinal artery aneurysm in aortic stenosis of different etiology: Report of three cases.

PubMed

Singh, Vivek; Naik, Suprava; Bhoi, Sanjeev K; Phadke, R V

2017-04-01

Isolated aneurysms of spinal arteries are rare. Spinal artery aneurysms are commonly found in association with spinal cord arteriovenous malformation and coarctation of aorta and rarely with aortic arch interruption and Klippel-Trenaunay syndrome. Spinal angiograms are the gold standard for diagnosing these spinal artery aneurysms but with the advances in computed tomography technology these aneurysms can also be very well demonstrated in computed tomography angiograms. We describe three cases of anterior spinal artery aneurysm, those are flow related aneurysms, associated with coarctation of aorta and with Takayasu arteritis.

Mesodermal expression of integrin α5β1 regulates neural crest development and cardiovascular morphogenesis

PubMed Central

Liang, Dong; Wang, Xia; Mittal, Ashok; Dhiman, Sonam; Hou, Shuan-Yu; Degenhardt, Karl; Astrof, Sophie

2014-01-01

Integrin α5-null embryos die in mid-gestation from severe defects in cardiovascular morphogenesis, which stem from defective development of the neural crest, heart and vasculature. To investigate the role of integrin α5β1 in cardiovascular development, we used the Mesp1Cre knock-in strain of mice to ablate integrin α5 in the anterior mesoderm, which gives rise to all of the cardiac and many of the vascular and muscle lineages in the anterior portion of the embryo. Surprisingly, we found that mutant embryos displayed numerous defects related to the abnormal development of the neural crest such as cleft palate, ventricular septal defect, abnormal development of hypoglossal nerves, and defective remodeling of the aortic arch arteries. We found that defects in arch artery remodeling stem from the role of mesodermal integrin α5β1 in neural crest proliferation and differentiation into vascular smooth muscle cells, while proliferation of pharyngeal mesoderm and differentiation of mesodermal derivatives into vascular smooth muscle cells was not defective. Taken together our studies demonstrate a requisite role for mesodermal integrin α5β1 in signaling between the mesoderm and the neural crest, thereby regulating neural crest-dependent morphogenesis of essential embryonic structures. PMID:25242040

A reappraisal of retrograde cerebral perfusion.

PubMed

Ueda, Yuichi

2013-05-01

Brain protection during aortic arch surgery by perfusing cold oxygenated blood into the superior vena cava was first reported by Lemole et al. In 1990 Ueda and associates first described the routine use of continuous retrograde cerebral perfusion (RCP) in thoracic aortic surgery for the purpose of cerebral protection during the interval of obligatory interruption of anterograde cerebral flow. The beneficial effects of RCP may be its ability to sustain brain hypothermia during hypothermic circulatory arrest (HCA) and removal of embolic material from the arterial circulation of the brain. RCP can offer effective brain protection during HCA for about 40 to 60 minutes. Animal experiments revealed that RCP provided inadequate cerebral perfusion and that neurological recovery was improved with selective antegrade cerebral perfusion (ACP), however, both RCP and ACP provide comparable clinical outcomes regarding both the mortality and stroke rates by risk-adjusted and case-matched comparative study. RCP still remains a valuable adjunct for brain protection during aortic arch repair in particular pathologies and patients.

A reappraisal of retrograde cerebral perfusion

PubMed Central

2013-01-01

Brain protection during aortic arch surgery by perfusing cold oxygenated blood into the superior vena cava was first reported by Lemole et al. In 1990 Ueda and associates first described the routine use of continuous retrograde cerebral perfusion (RCP) in thoracic aortic surgery for the purpose of cerebral protection during the interval of obligatory interruption of anterograde cerebral flow. The beneficial effects of RCP may be its ability to sustain brain hypothermia during hypothermic circulatory arrest (HCA) and removal of embolic material from the arterial circulation of the brain. RCP can offer effective brain protection during HCA for about 40 to 60 minutes. Animal experiments revealed that RCP provided inadequate cerebral perfusion and that neurological recovery was improved with selective antegrade cerebral perfusion (ACP), however, both RCP and ACP provide comparable clinical outcomes regarding both the mortality and stroke rates by risk-adjusted and case-matched comparative study. RCP still remains a valuable adjunct for brain protection during aortic arch repair in particular pathologies and patients. PMID:23977600

Fingerprints and cardiovascular risk. The San Valentino fingerprint vascular screening project (SanVal/FP).

PubMed

Belcaro, G; Cesarone, M R; Ledda, A; Cornelli, U; Dugall, M; Di Renzo, A; Hosoi, M; Stuard, S; Vinciguerra, G; Pellegrini, L; Gizzi, G

2008-10-01

Fingerprints (FP), characteristic of humans, are impressions due to skin marks (ridges) on fingertips. Ridges are present on fingers/hands forming curved lines of different sizes/patterns. The point where a line stops or splits is defined typica' (their number/amount constitute identification patterns). FP are permanent and unique. This study compared FP patterns with cardiovascular risk factors: 7 main types of FP were used: 1. Arch: lines form waves from one site to the other side. 2. Tentarch: like arches but with a rising stick in the middle. 3. Loop: lines coming from one site returning in the middle to the same site. 4. Double loop: like loops but with two loops inside: one standing, one hanging. 5. Pocked loop: like the loop but with a small circle in the turning point. 6. Whorl: lines make circles. 7. Mixed figure: composed of different figures. There are two kinds of real typica: A. Ending line; B. Splitting lines (bifurcations). Several combinations may result. Ultrasound evaluation of carotid/femoral arteries in asymptomatic subjects. Arteries were evaluated with high-resolution ultrasound at the bifurcations. Four classes were defined: 1: normal intima-media (IMT) complex; 2: IMT thickening; 3: non-stenosing plaques (<50% stenosis); 4: stenosing plaque (>50%). Subjects in classes 1, 2, 3 were included into the analysis made comparing FP patterns and ultrasound. For each FP pattern: A. the main proportion of subjects with cardiovacular risk factors (91%) had arches (41.2%) and loops (either single, 38.2% or double 11.7% for a total of 49.9%). B. The remaining classes were statistically less important. C. The number of ridges per square mm was comparable in all pattern classes. D. The analysis of typica and other ridges characteristics requires a more elaborated system. Future research must define simple, low cost screening methods for preselection of subjects at higher cardiovascular risk or for exclusion of low risk subjects. The evaluation of fingerprint pattern may be useful to define risk groups.

Four-dimensional ultrasonography of the fetal heart with spatiotemporal image correlation.

PubMed

Gonçalves, Luís F; Lee, Wesley; Chaiworapongsa, Tinnakorn; Espinoza, Jimmy; Schoen, Mary Lou; Falkensammer, Peter; Treadwell, Marjorie; Romero, Roberto

2003-12-01

This study was undertaken to describe a new technique for the examination of the fetal heart using four-dimensional ultrasonography with spatiotemporal image correlation (STIC). Volume data sets of the fetal heart were acquired with a new cardiac gating technique (STIC), which uses automated transverse and longitudinal sweeps of the anterior chest wall. These volumes were obtained from 69 fetuses: 35 normal, 16 with congenital anomalies not affecting the cardiovascular system, and 18 with cardiac abnormalities. Dynamic multiplanar slicing and surface rendering of cardiac structures were performed. To illustrate the STIC technique, two representative volumes from a normal fetus were compared with volumes obtained from fetuses with the following congenital heart anomalies: atrioventricular septal defect, tricuspid stenosis, tricuspid atresia, and interrupted inferior vena cava with abnormal venous drainage. Volume datasets obtained with a transverse sweep were utilized to demonstrate the cardiac chambers, moderator band, interatrial and interventricular septae, atrioventricular valves, pulmonary veins, and outflow tracts. With the use of a reference dot to navigate the four-chamber view, intracardiac structures could be simultaneously studied in three orthogonal planes. The same volume dataset was used for surface rendering of the atrioventricular valves. The aortic and ductal arches were best visualized when the original plane of acquisition was sagittal. Volumes could be interactively manipulated to simultaneously visualize both outflow tracts, in addition to the aortic and ductal arches. Novel views of specific structures were generated. For example, the location and extent of a ventricular septal defect was imaged in a sagittal view of the interventricular septum. Furthermore, surface-rendered images of the atrioventricular valves were employed to distinguish between normal and pathologic conditions. Representative video clips were posted on the Journal's Web site to demonstrate the diagnostic capabilities of this new technique. Dynamic multiplanar slicing and surface rendering of the fetal heart are feasible with STIC technology. One good quality volume dataset, obtained from a transverse sweep, can be used to examine the four-chamber view and the outflow tracts. This novel method may assist in the evaluation of fetal cardiac anatomy.

Side effects of therapy with prostaglandin E1 in infants with critical congenital heart disease.

PubMed

Lewis, A B; Freed, M D; Heymann, M A; Roehl, S L; Kensey, R C

1981-11-01

The case reports of 492 infants with critical congenital cardiac disease treated with prostaglandin E1 (PGE1) were reviewed to determine the nature and incidence of intercurrent medical events. Forty-three percent of the infants had at least one such event, but only half of these were related to PGE1 and the majority required only minor changes in management. Cardiovascular events were the most common (18% incidence), with cutaneous vasodilation and edema occurring more frequently during intraaortic infusion than during i.v. infusion. Central nervous system events were reported in 16% of the patients. Respiratory depression was reported in 12%, and was particularly common in infants weighing less than 2.0 kg at birth (42%). Hematologic, infectious and renal events appeared for the most part to be unrelated to PGE1. The overall mortality (excluding 19 patients with hypoplastic left-heart syndrome) was 31%; the mortality for the patients with critical coarctation or interruption of the aortic arch was nearly twice that for the cyanotic infants (50% vs 27%). No death was attributed to PGE1 administration. During infusion of PGE1, arterial blood pressure and respiratory activity should be monitored carefully and appropriate supportive steps taken if hypotension or respiratory depression occurs. The development of fever or jitteriness may require reduction of the infusion rate and, in view of the possible increased incidence of infections, the prophylactic use of antibiotics is recommended.

Aortic arch calcification detectable on chest X-ray films is associated with plasma diacron-reactive oxygen metabolites in patients with type 2 diabetes but without cardiovascular disease.

PubMed

Watanabe, Kentaro; Ohara, Makoto; Suzuki, Tatsuya; Ouchi, Motoshi; Suzuki, Kazunari; Hashimoto, Masao; Saigusa, Taro; Aoyama, Junya; Nakano, Hiroshi; Oba, Kenzo

2013-01-01

This study aimed to evaluate the relationship between aortic arch calcification (AAC) detectable on chest X-ray films and plasma diacron-reactive oxygen metabolites (d-ROMs) in patients with type 2 diabetes but without cardiovascular disease. Forty-nine patients with type 2 diabetes but without cardiovascular disease were evaluated with chest X-ray examinations and divided into those with AAC (n=26) and those without AAC (n=23). Biochemical variables, including plasma levels of d-ROMS, high-sensitivity C-reactive protein (hsCRP), plasminogen activator inhibitor-1 (PAI-1), and lipoprotein(a) (Lp(a)), were evaluated after an overnight fast. The relationships of AAC with both inflammation and oxidative-stress variables were evaluated. The plasma level of d-ROMs in subjects with AAC was significantly higher than that in subjects without AAC, whereas plasma levels of hsCRP, PAI-1, and Lp(a) in subjects with AAC were higher, but not significantly so, than those in subjects without AAC. Multivariate linear regression analysis with AAC grade as the dependent variable and plasma levels of d-ROMs, hsCRP, PAI-1, or Lp(a) as independent variables demonstrated a significant association of AAC grade with plasma levels of d-ROMs but not with plasma levels of hsCRP, PAI-1, or Lp(a). The plasma level of d-ROMs is associated with AAC in patients with type 2 diabetes but without cardiovascular disease. Hence, the results of the present study suggest that AAC in these patients is strongly associated with oxidative stress. Furthermore, patients with type 2 diabetes and AAC may be at high risk for the development and progression of various diabetic complications induced by oxidative stress.

Induced Pectus Carinatum.

PubMed

Maddali, Madan Mohan; Valliattu, John; Kandachar, Pranav Subbaraya; Thomas, Eapen; Nishant, Arora Ram

2016-05-01

During the surgical repair of a truncus arteriosus with aortic arch interruption and pulmonary artery origin stenosis, a Contegra conduit was implanted as part of reconstruction of the pulmonary artery in a small infant. There was a mismatch between the conduit size and the patient that resulted in protrusion of the conduit between the sternal edges. To accommodate the conduit inside the thoracic cavity, traction was applied to the sternum that was gradually released over a period of time guided by transesophageal echocardiography-derived cardiac output data, as well as continuous hemodynamic parameters. doi: 10.1111/jocs.12734 (J Card Surg 2016;31:357-360). © 2016 Wiley Periodicals, Inc.

[Dental alveolar bone and dental arch remodeling in children: orthodontic diagnosis and treatments based on individual child arch development].

PubMed

Xiaobing, Li

2016-12-01

The etiology of malocclusions basically involves both congenital and environmental factors. Malocclusion is the result of the abnormal development of the orofacial complex (including tooth, dental alveolar bone, upper and lower jaws). Early orthodontic interceptive treatments involve the elimination of all congenital and environmental factors that contribute to the malformation of the orofacial complex, as well as interrupt the deviated development of the orofacial complex and the occlusion. Early orthodontic interceptive treatments mainly aim to use children's growth potential to correct abnormal developments of occlusions and orthodontically treat malocclusions more efficiently. The early orthodontic interceptive treatments include correcting the child's bad oral habits, training the abnormal functioned para-oral muscles, maintaining the normal eruptions of succeeding permanent teeth, applying interceptive treatments to the mal-developed teeth, and employing functional orthopedic treatments for abnormal growths of the upper and lower jaws. In orthodontics, correcting mal-positioned teeth is called orthodontic treatment, while rectifying the abnormal relationships of the upper and lower jaws is called functional orthopedic treatment. However, no clear definition is available as regards to the early orthodontic interceptive treatment of malocclusions caused by the deviated development of the dental alveolar bone. This new theory of "early dental alveolar bone and dental arch remodeling technique" was proposed by Professor Li Xiaobing of the Department of Pediatric Dentistry, Faculty of Pediatric Dentistry and Orthodontics in West China Hospital of Stomatology through his clinical analyses and investigation of his early orthodontic interceptive treatments. He defined the early orthodontic corrections of abnormal growth of dental alveolar bone as "remodel". The "early dental alveolar bone and dental arch remodeling theory and technique" is proved useful in malocclusion diagnosis and treatment planning during early orthodontic interceptive treatment with malformed dental arch. With the development of the theory and technique, the author intended to prevent and intercept the malocclusion development more effectively and efficiently. This review presents the development and clinical usages of the theory which to provide a new vision in the analysis of malocclusions on the basis of the developmental mechanism of the alveolar bone and dental arch. With clinical case illustration, the author demonstrateshis successful orthodontic clinical practices with this theory, which may contribute to the development of contemporary orthodontic theories and techniques.

Variations in plantar pressure variables across five cardiovascular exercises.

PubMed

Burnfield, Judith M; Jorde, Amy G; Augustin, Tanner R; Augustin, Tate A; Bashford, Gregory R

2007-11-01

To quantify variations in plantar pressure variables in healthy adults across five cardiovascular exercises. Ten young (19-35 yr old) and 10 middle-aged (45-60 yr old) individuals participated. After equipment familiarization, plantar pressure data were recorded during walking, running, elliptical training, stair climbing, and recumbent biking. Separate one-way analyses of variance with repeated measures identified significant differences in pressure variables across exercises and between age groups under the forefoot, arch, and heel. Forefoot: Peak pressures were higher during walking (253 kPa), running (251 kPa), and elliptical training (213 kPa) than stair climbing (130 kPa) and recumbent biking (41 kPa; P < or = 0.001). Biking pressures were lower than all other conditions (P < 0.001). Arch: Pressures were higher during running (144 kPa) compared with all other conditions (P < or = 0.001). Intermediate-level pressures during walking (119 kPa) and elliptical training (102 kPa) exceeded those during stair climbing (80 kPa; P < or = 0.002). Pressures were lowest during recumbent biking (33 kPa; P < 0.001). Heel: Pressures were highest during walking (215 kPa) and running (188 kPa), exceeding those recorded during all other activities (P < 0.001). Moderate elliptical training pressures (94 kPa) surpassed stair climbing values (66 kPa; P = 0.014). Pressures were lowest during recumbent biking (25 kPa; P < 0.001). The only significant difference identified between age groups was a larger arch contact area in the young compared with middle-aged, when averaged across exercises (P = 0.011). When protection of the forefoot is important (e.g., diabetic foot neuropathies), biking and stair climbing offer optimal pressure reductions. If protecting the heel from high pressures and forces is warranted, recumbent biking, stair climbing, and elliptical training provide greater relief.

Alveolar gas composition during maximal and interrupted apnoeas in ambient air and pure oxygen.

PubMed

Fagoni, Nazzareno; Taboni, Anna; Vinetti, Giovanni; Bottarelli, Sara; Moia, Christian; Bringard, Aurélién; Ferretti, Guido

2017-01-01

We tested the hypothesis that the alveolar gas composition at the transition between the steady phase II (φ2) and the dynamic phase III (φ3) of the cardiovascular response to apnoea may lay on the physiological breaking point curve (Lin et al., 1974). Twelve elite divers performed maximal and φ2-interrupted apnoeas, in air and pure oxygen. We recorded beat-by-beat arterial blood pressure and heart rate; we measured alveolar oxygen and carbon dioxide pressures (P A O 2 and P A CO 2 , respectively) before and after apnoeas; we calculated the P A CO 2 difference between the end and the beginning of apnoeas (ΔP A CO 2 ). Cardiovascular responses to apnoea were similar compared to previous studies. P A O 2 and P A CO 2 at the end of φ2-interrupted apnoeas, corresponded to those reported at the physiological breaking point. For maximal apnoeas, P A CO 2 was less than reported by Lin et al. (1974). ΔP A CO 2 was higher in oxygen than in air. The transition between φ2 and φ3 corresponds indeed to the physiological breaking point. We attribute this transition to ΔP A CO 2 , rather than the absolute P A CO 2 values, both in air and oxygen apnoeas. Copyright © 2016 Elsevier B.V. All rights reserved.

CXCL12-CXCR4 signalling plays an essential role in proper patterning of aortic arch and pulmonary arteries.

PubMed

Kim, Bo-Gyeong; Kim, Yong Hwan; Stanley, Edward L; Garrido-Martin, Eva M; Lee, Young Jae; Oh, S Paul

2017-11-01

Chemokine CXCL12 (stromal derived factor 1: SDF1) has been shown to play important roles in various processes of cardiovascular development. In recent avian studies, CXCL12 signalling has been implicated in guidance of cardiac neural crest cells for their participation in the development of outflow tract and cardiac septum. The goal of this study is to investigate the extent to which CXCL12 signalling contribute to the development of aortic arch and pulmonary arteries in mammals. Novel Cxcl12-LacZ reporter and conditional alleles were generated. Using whole mount X-gal staining with the reporter allele and vascular casting techniques, we show that the domain branching pattern of pulmonary arteries in Cxcl12-null mice is completely disrupted and discordant with that of pulmonary veins and airways. Cxcl12-null mice also displayed abnormal and superfluous arterial branches from the aortic arch. The early steps of pharyngeal arch remodelling in Cxcl12-null mice appeared to be unaffected, but vertebral arteries were often missing and prominent aberrant arteries were present parallel to carotid arteries or trachea, similar to aberrant vertebral artery or thyroid ima artery, respectively. Analysis with computed tomography not only confirmed the results from vascular casting studies but also identified abnormal systemic arterial supply to lungs in the Cxcl12-null mice. Tie2-Cre mediated Cxcr4 deletion phenocopied the Cxcl12-null phenotypes, indicating that CXCR4 is the primary receptor for arterial patterning, whereas Cxcl12 or Cxcr4 deletion by Wnt1-Cre did not affect aortic arch patterning. CXCL12-CXCR4 signalling is essential for the correct patterning of aortic arches and pulmonary arteries during development. Superfluous arteries in Cxcl12-null lungs and the aortic arch infer a role of CXCL12 in protecting arteries from uncontrolled sprouting during development of the arterial system. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

Scottish Keep Well health check programme: an interrupted time series analysis.

PubMed

Geue, Claudia; Lewsey, James D; MacKay, Daniel F; Antony, Grace; Fischbacher, Colin M; Muirie, Jill; McCartney, Gerard

2016-09-01

Effective interventions are available to reduce cardiovascular risk. Recently, health check programmes have been implemented to target those at high risk of cardiovascular disease (CVD), but there is much debate whether these are likely to be effective at population level. This paper evaluates the impact of wave 1 of Keep Well, a Scottish health check programme, on cardiovascular outcomes. Interrupted time series analyses were employed, comparing trends in outcomes in participating and non-participating practices before and after the introduction of health checks. Health outcomes are defined as CVD mortality, incident hospitalisations and prescribing of cardiovascular drugs. After accounting for secular trends and seasonal variation, coronary heart disease mortality and hospitalisations changed by 0.4% (95% CI -5.2% to 6.3%) and -1.1% (-3.4% to 1.3%) in Keep Well practices and by -0.3% (-2.7% to 2.2%) and -0.1% (-1.8% to 1.7%) in non-Keep Well practices, respectively, following the intervention. Adjusted changes in prescribing in Keep Well and non-Keep Well practices were 0.4% (-10.4% to 12.5%) and -1.5% (-9.4% to 7.2%) for statins; -2.5% (-12.3% to 8.4%) and -1.6% (-7.1% to 4.3%) for antihypertensive drugs; and -0.9% (-6.5% to 5.0%) and -2.4% (-10.1% to 6.0%) for antiplatelet drugs. Any impact of the Keep Well health check intervention on CVD outcomes and prescribing in Scotland was very small. Findings do not support the use of the screening approach used by current health check programmes to address CVD. We used an interrupted time series method, but evaluation methods based on randomisation are feasible and preferable and would have allowed more reliable conclusions. These should be considered more often by policymakers at an early stage in programme design when there is uncertainty regarding programme effectiveness. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effect of cannula shape on aortic wall and flow turbulence: hydrodynamic study during extracorporeal circulation in mock thoracic aorta.

PubMed

Minakawa, Masahito; Fukuda, Ikuo; Yamazaki, Junichi; Fukui, Kozo; Yanaoka, Hideki; Inamura, Takao

2007-12-01

This study was designed to analyze flow pattern, velocity, and strain on the aortic wall of a glass aortic model during extracorporeal circulation, and to elucidate the characteristics of flow pattern in four aortic cannulas. Different patterns of large vortices and helical flow were made by each cannula. The high-velocity flow (0.6 m/s) was observed in end-hole cannula, causing high strain rate tensor (0.3~0.4 without unit) on the aortic arch. In dispersion cannula, a decreased strain rate tensor (less than 0.1) was found on the outer curvature of the aortic arch. In Soft-flow cannula (3M Cardiovascular, Ann Arbor, MI, USA), further decreased flow velocity (0.2 m/s) and strain (less than 0.2) were observed. In Select 3D cannula (Medtronic, Inc., Minneapolis, MN, USA), a high strain (0.4~0.5) was observed along the inner curvature of the aortic arch. In conclusion, end-hole cannula should not be used in atherosclerotic aorta. Particular attention should be paid both for selection of cannulas and cannulation site based on this result.

Blood flow characteristics in the aortic arch

NASA Astrophysics Data System (ADS)

Prahl Wittberg, Lisa; van Wyk, Stevin; Mihaiescu, Mihai; Fuchs, Laszlo; Gutmark, Ephraim; Backeljauw, Philippe; Gutmark-Little, Iris

2012-11-01

The purpose with this study is to investigate the flow characteristics of blood in the aortic arch. Cardiovascular diseases are associated with specific locations in the arterial tree. Considering atherogenesis, it is claimed that the Wall Shear Stress (WSS) along with its temporal and spatial gradients play an important role in the development of the disease. The WSS is determined by the local flow characteristics, that in turn depends on the geometry as well as the rheological properties of blood. In this numerical work, the time dependent fluid flow during the entire cardiac cycle is fully resolved. The Quemada model is applied to account for the non-Newtonian properties of blood, an empirical model valid for different Red Blood Cell loading. Data obtained through Cardiac Magnetic Resonance Imaging have been used in order to reconstruct geometries of the the aortic arch. Here, three different geometries are studied out of which two display malformations that can be found in patients having the genetic disorder Turner's syndrome. The simulations show a highly complex flow with regions of secondary flow that is enhanced for the diseased aortas. The financial support from the Swedish Research Council (VR) and the Sweden-America Foundation is gratefully acknowledged.

Full blown cardiovascular syphilis with aneurysm of the innominate artery.

PubMed

Roberts, William Clifford; Lensing, Forrester Dubus; Kourlis, Harry; Ko, Jong Mi; Newberry, Jonathan Warren; Smerud, Michael John; Burton, Elizabeth C; Hebeler, Robert Frederick

2009-12-01

The investigators report the case of a 44-year-old man who presented acutely and was found to have saccular aneurysm of the innominate artery, narrowed or totally occluded aortic arch arteries, and marked thickening of the thoracic aorta except for the wall behind the sinuses of Valsalva. The abdominal aorta was entirely normal. Results of the serologic test for syphilis were strongly positive. Because cardiovascular syphilis appears to be a disease that affects the vasa vasora and because these channels are limited to the thoracic aorta, the abdominal aorta is uninvolved, as demonstrated so nicely in the patient described in this case report. Because most patients with cardiovascular syphilis are much older than the patient described, it is unusual to see a perfectly normal abdominal aorta, as in the present patient. In conclusion, syphilis producing aneurysm of the innominate artery is unusual but is always associated with syphilitic involvement of the thoracic aorta.

``Smart'' baroreception along the aortic arch, with reference to essential hypertension

NASA Astrophysics Data System (ADS)

Kember, G. C.; Zamir, M.; Armour, J. A.

2004-11-01

Beat-to-beat regulation of heart rate is dependent upon sensing of local stretching or local “disortion” by aortic baroreceptors. Distortions of the aortic wall are due mainly to left ventricular output and to reflected waves arising from the arterial tree. Distortions are generally believed to be useful in cardiac control since stretch receptors or aortic baroreceptors embedded in the adventitia of the aortic wall, transduce the distortions to cardiovascular neural reflex pathways responsible for beat-to-beat regulation of heart rate. Aortic neuroanatomy studies have also found a continuous strip of mechanosensory neurites spread along the aortic inner arch. Although their purpose is now unknown, such a combined sensing capacity would allow measurement of the space and time dependence of inner arch wall distortions due, among other things, to traveling waves associated with pulsatile flow in an elastic tube. We call this sensing capability-“smart baroreception.” In this paper we use an arterial tree model to show that the cumulative effects of wave reflections, from many sites far downstream, have a surprisingly pronounced effect on the pressure distribution in the root segment of the tree. By this mechanism global hemodynamics can be focused by wave reflections back to the aortic arch, where they can rapidly impact cardiac control via smart baroreception. Such sensing is likely important to maintain efficient heart function. However, alterations in the arterial tree due to aging and other natural processes can lead in such a system to altered cardiac control and essential hypertension.

[Etiology and airway management in children with tracheobronchomalacia].

PubMed

Yin, Yong; Schonfeld, Tommy; Chen, Tong-xin

2009-02-01

To investigate etiology and airway management in children with tracheobronchomalacia. Bronchoscopic examinations were performed in 671 children. The cases with tracheomalacia and bronchomalacia were analyzed in etiopathogenesis and summarized their therapy simultaneously. Bronchoscopic examination indicated tracheomalacia and bronchomalacia in 148 cases, tracheomalacia in 77 cases and bronchomalacia in 71 cases. Among the cases with tracheomalacia, compression by vascular rings was found in 46 cases, incorporated congenital esophageal atresia with tracheoesophageal fistula was found in 5 cases, tracheomalacia was associated with tracheostoma and mechanical ventilation in 6 cases, with congenital airway malformation in 11 cases and isolated tracheomalacia was found in 4 cases. Among the cases with bronchomalacia, incorporated congenital cardiovascular malformation was found in 64 cases, congenital airway malformation in 6 cases and isolated bronchomalacia in 1 case. Ten children with anomalous innominate artery underwent aortopexy, twelve children with dextro-aorta arch with concomitant aberrant left subclavian artery and double aorta underwent arches vascular ring lysis, six children with pulmonary sling underwent plasty. Severe malacia segments were resected directly in four children during operation. Mechanical ventilation was performed in 38 children. Tracheostoma was performed in 4 children to treat tracheomalacia and bronchomalacia, it could relieve symptom to a certain extent. In 2 children metal stents were inserted into the bronchus for the treatment of bronchomalacia, one was successful and the other needed re-insertion of stent again, these two patients underwent balloon-dilatation in distal part of stent afterwards. The congenital cardiovascular malformation was the main reason to develop tracheobronchomalacia in children. The symptom of majority of the cases with cardiovascular malformation would be improved within 6 months after surgical intervention. In severe cases, treatments included mechanical ventilation and tracheostoma. Stenting could be applied in refractory cases, but it had certain limitations.

Micro-computed Tomography Provides High Accuracy Congenital Heart Disease Diagnosis in Neonatal and Fetal Mice

PubMed Central

Kim, Andrew J.; Francis, Richard; Liu, Xiaoqin; Devine, William A.; Ramirez, Ricardo; Anderton, Shane J.; Wong, Li Yin; Faruque, Fahim; Gabriel, George C.; Leatherbury, Linda; Tobita, Kimimasa; Lo, Cecilia W.

2013-01-01

Background Mice are well suited for modeling human congenital heart defects (CHD), given their four-chamber cardiac anatomy. However, mice with CHD invariably die prenatally/neonatally, causing CHD phenotypes to be missed. Therefore, we investigated the efficacy of noninvasive micro-computed tomography (micro-CT) to screen for CHD in stillborn/fetal mice. These studies were carried out using chemically mutagenized mice expected to be enriched for birth defects including CHD. Methods and Results Stillborn/fetal mice obtained from the breeding of N-ethyl-N-nitrosourea (ENU) mutagenized mice were formalin-fixed and stained with iodine, then micro-CT scanned. Those diagnosed with CHD and some CHD-negative pups were necropsied. A subset of these were further analyzed by histopathology to confirm the CHD/no-CHD diagnosis. Micro-CT scanning of 2105 fetal/newborn mice revealed an abundance of ventricular septal defects (VSD) (n=307). Overall, we observed an accuracy of 89.8% for VSD diagnosis. Outflow tract anomalies identified by micro-CT included double outlet right ventricle (n=36), transposition of the great arteries (n=14), and persistent truncus arteriosus (n=3). These were diagnosed with a 97.4% accuracy. Aortic arch anomalies also were readily detected with an overall 99.6% accuracy. This included right aortic arch (n=28) and coarctation/interrupted aortic arch (n=12). Also detected by micro-CT were atrioventricular septal defects (n=22), tricuspid hypoplasia/atresia (n=13), and coronary artery fistulas (n=16). They yielded accuracies of 98.9%, 100%, and 97.8% respectively. Conclusions Contrast enhanced micro-CT imaging in neonatal/fetal mice can reliably detect a wide spectrum of CHD. We conclude micro-CT imaging can be used for routine rapid assessments of structural heart defects in fetal/newborn mice. PMID:23759365

Malocclusion in Early Anatomically Modern Human: A Reflection on the Etiology of Modern Dental Misalignment

PubMed Central

Sarig, Rachel; Slon, Viviane; Abbas, Janan; May, Hila; Shpack, Nir; Vardimon, Alexander Dan; Hershkovitz, Israel

2013-01-01

Malocclusions are common in modern populations. Yet, as the study of occlusion requires an almost intact dentition in both the maxilla and mandible, searching for the ultimate cause of malocclusion is a challenge: relatively little ancient material is available for research on occlusal states. The Qafzeh 9 skull is unique, as its preserved dentition allowed us to investigate the presence and manifestations of malocclusion. The aim of this study was thus to examine the occlusal condition in the Qafzeh 9 specimen in light of modern knowledge regarding the etiology of malocclusion. We revealed a pathologic occlusion in the Qafzeh 9 skull that probably originated in the early developmental stage of the dentition, and was aggravated by forces applied by mastication. When arch continuity is interrupted due to misalignment of teeth as in this case, force transmission is not equal on both sides, causing intra-arch outcomes such as mesialization of the teeth, midline deviation, rotations and the aggravation of crowding. All are evident in the Qafzeh 9 skull: the midline deviates to the left; the incisors rotate mesio-buccally; the left segment is constricted; the left first molar is buccally positioned and the left premolars palatally tilted. The inter-arch evaluation revealed anterior cross bite with functional shift that might affect force transmission and bite force. In conclusion, the findings of the current study suggest that malocclusion of developmental origin was already present in early anatomically modern humans (AMH) (the present case being the oldest known case, dated to ca. 100,000 years); that there is no basis to the notion that early AMH had a better adjustment between teeth and jaw size; and that jaw-teeth size discrepancy could be found in prehistoric populations and is not a recent phenomenon. PMID:24278319

Design and Development of a Series Switch for High Voltage in RF Heating

NASA Astrophysics Data System (ADS)

Patel, Himanshu K.; Shah, Deep; Thacker, Mauli; Shah, Atman

2013-02-01

Plasma is the fourth state of matter. To sustain plasma in its ionic form very high temperature is essential. RF heating systems are used to provide the required temperature. Arching phenomenon in these systems can cause enormous damage to the RF tube. Heavy current flows across the anode-cathode junction, which need to be suppressed in minimal time for its protection. Fast-switching circuit breakers are used to cut-off the load from the supply in cases of arching. The crowbar interrupts the connection between the high voltage power supply (HVPS) and the RF tube for a temporary period between which the series switch has to open. The crowbar shunts the current across the load but in the process leads to short circuiting the HVPS. Thus, to protect the load as well as the HVPS a series switch is necessary. This paper presents the design and development of high voltage Series Switch for the high power switching applications. Fiber optic based Optimum triggering scheme is designed and tested to restrict the time delay well within the stipulated limits. The design is well supported with the experimental results for the whole set-up along with the series switch at various voltage level before its approval for operation at 5.2 kV.

Association between arterial calcifications and nonlacunar and lacunar ischemic strokes.

PubMed

van Dijk, Anouk C; Fonville, Susanne; Zadi, Taihra; van Hattem, Antonius M G; Saiedie, Ghesrouw; Koudstaal, Peter J; van der Lugt, Aad

2014-03-01

Nonlacunar cerebral infarcts are presumed to be caused by thromboembolism from the heart or extracranial arteries, whereas lacunar infarcts are thought to be caused by small vessel disease. We investigated to what extent arterial calcifications differ between nonlacunar and lacunar ischemic strokes. We studied 820 consecutive patients with transient ischemic attack or ischemic stroke in the anterior circulation who underwent multidetector computed tomography angiography and had no rare cause of stroke. The presence of likely cardioembolic pathogenesis was determined according to the Trial of Org 10172 in Acute Stroke Treatment criteria. The remaining 708 patients were categorized as nonlacunar or lacunar strokes, either transient ischemic attacks or strokes, based on clinical symptoms corrected by brain imaging results. We measured volume of calcifications in the aortic arch, symptomatic extracranial and intracranial carotid artery using multidetector computed tomography angiography. The difference in calcifications between nonlacunar and lacunar strokes was assessed with a multivariable logistic regression analysis. We adjusted for degree of symptomatic carotid artery stenosis and cardiovascular risk factors. We found an independent association between volume of aortic arch calcifications and nonlacunar ischemic strokes (adjusted odds ratio [95% confidence interval], 1.11 [1.02-1.21]). No independent associations between extracranial and intracranial carotid artery calcifications and nonlacunar strokes were present. The only difference we found between nonlacunar and lacunar strokes was a higher calcification volume in the aortic arch in nonlacunar strokes. Our findings only partially confirm the notion of distinct etiologies and suggest that the potential role of other plaque components, plaque morphology, and aortic arch calcifications in ischemic stroke subtypes awaits further evaluation.

Ventriculoarterial coupling in palliated hypoplastic left heart syndrome: Noninvasive assessment of the effects of surgical arch reconstruction and shunt type.

PubMed

Biglino, Giovanni; Giardini, Alessandro; Ntsinjana, Hopewell N; Schievano, Silvia; Hsia, Tain-Yen; Taylor, Andrew M

2014-10-01

To assess the coupling efficiency in hypoplastic left heart syndrome, considering the effect of surgical arch reconstruction and the shunt type received during the Norwood procedure. Ventriculoarterial coupling was assessed before Fontan completion in 32 patients with hypoplastic left heart syndrome (19 modified Blalock-Taussig and 13 Sano shunts at stage 1). Cardiovascular magnetic resonance data were analyzed, deriving functional parameters and 3-dimensional volumes. Dimensional indexes were computed from 3-dimensional data sets as the area ratio of the isthmus to the descending aorta (Risthmus) and the isthmus to surgically enlarged transverse arch (Rarch). Wave intensity was calculated from cardiac magnetic resonance, using the peaks of the forward compression and expansion waves in early and late systole as surrogate indicators of ventriculoarterial coupling. Aortic distensibility (3.6±2.7×10(-3) 1/mm Hg) was not associated with the time elapsed from stage 1 palliation (P=.94), suggesting an early loss of elasticity that did not progress thereafter. Risthmus was 1.0±0.4, and Rarch was 0.3±0.1, indicating the dilated reconstructed arch was the main anatomic feature. The forward compression wave correlated significantly with Rarch (R2=0.23, P=.006) but not with Risthmus (R2<0.01, P=.63). Patients with a reduced ejection fraction exhibited a larger ventricular mass (R2=0.28, P=.003). The Sano shunt patients had a lower ejection fraction (51%±6% vs 57%±6%, P=.02); however, neither the forward compression nor expansion wave varied significantly between shunt type or the other functional parameters. Ventriculoarterial coupling in operated hypoplastic left heart syndrome was affected by aortic arch size mismatch but not by the type of shunt placed at the Norwood operation. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Natural products targeting ER stress pathway for the treatment of cardiovascular diseases.

PubMed

Choy, Ker Woon; Murugan, Dharmani; Mustafa, Mohd Rais

2018-04-21

Endoplasmic reticulum (ER) is the main organelle for the synthesis, folding, and processing of secretory and transmembrane proteins. Pathological stimuli including hypoxia, ischaemia, inflammation and oxidative stress interrupt the homeostatic function of ER, leading to accumulation of unfolded proteins, a condition referred to as ER stress. ER stress triggers a complex signalling network referred as the unfolded protein response (UPR). Extensive studies have demonstrated that ER stress plays an important role in the pathogenesis of various cardiovascular diseases such as heart failure, ischemic heart disease and atherosclerosis. The importance of natural products in modern medicine are well recognized and continues to be of interests as a source of novel lead compounds. Natural products targeting components of UPR and reducing ER stress offers an innovative strategic approach to treat cardiovascular diseases. In this review, we discussed several therapeutic interventions using natural products with potential cardiovascular protective properties targeting ER stress signalling pathways. Copyright © 2018 Elsevier Ltd. All rights reserved.

Stent Repair for Complex Coarctation of Aorta.

PubMed

Suárez de Lezo, José; Romero, Miguel; Pan, Manuel; Suárez de Lezo, Javier; Segura, José; Ojeda, Soledad; Pavlovic, Djordje; Mazuelos, Francisco; López Aguilera, José; Espejo Perez, Simona

2015-08-24

This study sought to determine whether several anatomic or evolving characteristics of the coarctation may create challenging conditions for treatment. Stent repair of coarctation of aorta is an alternative to surgical correction. We analyzed our 21-year experience in the percutaneous treatment of complex coarctation of aorta. Adverse conditions for treatment were as follow: 1) complete interruption of the aortic arch (n = 11); 2) associated aneurysm (n = 18); 3) complex stenosis (n = 30); and 4) the need for re-expansion and/or restenting (n = 21). Twenty patients (33%) belonged to more than 1 group. Ten interruptions were type A and 1 was type B. The mean length of the interrupted aorta was 9 ± 11 mm. The associated aneurysms were native in 8 patients and after previous intervention in 10 patients. Aneurysm shapes were fusiform in 8 patients and saccular in 10. The following characteristics defined complex stenosis as long diffuse stenosis, very tortuous coarctation, or stenosis involving a main branch or an unusual location. Patients previously stented at an early age, required re-expansion and/or restenting after reaching 16 ± 5 years of age. Two patients had died by 1-month follow-up. The remaining 58 patients did well and were followed-up for a mean period of 10 ± 6 years. Late adverse events occurred in 3 patients (5%). All remaining patients are symptom-free, with normal baseline blood pressure. Imaging techniques revealed good patency at follow-up without associated aneurysm or restenosis. The actuarial survival free probability of all complex patients at 15 years was 92%. Stent repair of complex coarctation of aorta is feasible and safe. Initial results are maintained at later follow-up. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Cardiac Teratogenicity in Mouse Maternal Phenylketonuria: Defining phenotype parameters and genetic background influences

PubMed Central

Seagraves, Nikki J.; McBride, Kim L.

2012-01-01

Maternal phenylketonuria (MPKU) is a syndrome including cardiovascular malformations (CVMs), microcephaly, intellectual impairment, and small for gestational age, caused by in-utero exposure to elevated serum phenylalanine (Phe) due to PKU in the mother. It is becoming a public health concern as more women with PKU reach child bearing age. Although a mouse model of PKU, BTBR Pahenu2, has been available for 20 years, it has not been well utilized for studying MPKU. We used this model to delineate critical parameters in Phe cardiovascular teratogenicity and study the effect of genetic background. Dosing and timing experiments were performed with the BTBR Pahenu2 mouse. A dose response curve was noted, with CVM rates at maternal serum Phe levels <360 μM (control), 360 – 600 μM (low), 600 – 900 μM (mid), and >900μM (high) of 11.86%, 16.67%, 30.86%, and 46.67% respectively. A variety of CVMs were noted on the BTBR background, including double outlet right ventricle (DORV), aortic arch artery (AAA)abnormalities, and ventricular septal defects (VSDs). Timed exposure experiments identified a teratogenic window from embryonic day 8.5-13.5, with higher rates of conotruncal and valve defects occurring in early exposure time and persistent truncus arteriosus (PTA) and aortic arch branching abnormalities occurring with late exposure. Compared to the BTBR strain, N10+ Pahenu2 congenics on the C3H/HeJ background had higher rates of CVMs in general and propensity to left ventricular outflow tract (LVOT) malformations, while the C57B/L6 background had similar CVM rates but predominately AAA abnormalities. We have delineated key parameters of Phe cardiovascular teratogenicity, demonstrated the utility of this MPKU model on different mouse strains, and shown how genetic background profoundly affects the phenotype. PMID:22951387

Cardiovascular operations for Loeys-Dietz syndrome: Intermediate-term results.

PubMed

Patel, Nishant D; Crawford, Todd; Magruder, J Trent; Alejo, Diane E; Hibino, Narutoshi; Black, James; Dietz, Harry C; Vricella, Luca A; Cameron, Duke E

2017-02-01

Early experience with Loeys-Dietz syndrome (LDS) suggested an aggressive aortopathy with high risk of aneurysm dissection and rupture at young ages and at smaller aortic diameters than in other connective tissue disorders. We reviewed our experience with LDS to re-examine our indications and outcomes of surgical management. We reviewed all patients with a diagnosis of LDS who underwent cardiovascular surgery at our institution. The primary endpoint was mortality, and secondary endpoints included postoperative complications and need for reintervention. Seventy-nine operated patients with LDS were identified. Mean age at first operation was 25 years, 39 (49%) were female, and 38 (48%) were children (age <18 years). Six (8%) patients presented with acute dissection. Five (6%) patients had a bicuspid aortic valve, and all presented with an ascending aortic aneurysm with a mean root diameter of 3.5cm. Twenty (25%) patients had a previous sternotomy. Sixty-five (82%) patients underwent aortic root replacement, of whom 52 underwent a valve-sparing operation and 4 had concomitant arch replacement. Mean aortic root diameter in this group was 4.2 cm. Nine (11%) patients underwent aortic arch replacement, 2 (3%) had isolated ascending aorta replacement, and 3 (4%) underwent open thoracoabdominal repair. There were 2 (3%) operative and 8 late deaths. Nineteen patients underwent subsequent operations for late aneurysm and/or dissection. Mean follow-up was 6 years (range 0-24 years). Kaplan-Meier survival was 88% at 10 years. Growing experience with LDS has confirmed early impressions of its aggressive nature and proclivity toward aortic catastrophe. Surgical outcomes are favorable, but reintervention rates are high. Meticulous follow-up with cardiovascular surveillance imaging remain important for management, particularly as clinical LDS subtypes are characterized and more tailored treatment is developed. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Ascending aortic aneurysm causing hoarse voice: a variant of Ortner's syndrome

PubMed Central

Eccles, Sinan Robert; Banks, John; Kumar, Pankaj

2012-01-01

A 68-year-old man with a persistent hoarse voice was found to have a left vocal cord paralysis. Clinical examination revealed signs consistent with aortic regurgitation. Subsequent investigation revealed an ascending aortic aneurysm. He underwent aortic root and ascending aorta replacement and his hoarseness improved. Ortner's syndrome refers to hoarseness due to recurrent laryngeal nerve palsy secondary to a cardiovascular abnormality. Recurrent laryngeal nerve palsy due to aneurysmal dilation of the ascending aorta is extremely rare, with aneurysms of the aortic arch being a more common cause. PMID:23060380

Ischemic stroke risk reduction following cardiac surgery by carotid compression

NASA Astrophysics Data System (ADS)

Isingoma, Paul

Every year over 500,000 cardiovascular procedures requiring cardiopulmonary bypass (CPB) are performed in the United States. CPB is a technique that temporarily takes over the function of the heart and lungs during surgery, maintaining the circulation of blood and the oxygen content of the body. During CPB, an aortic cross-clamp is used to clamp the aorta and separate the systemic circulation from the outflow of the heart. Unfortunately, these procedures have been found to cause most cerebral emboli, which produce clinical, subclinical and silent neurologic injuries. Many clinical neurologic injuries occur in the postoperative period, with over 20% of the clinical strokes occurring during this period. In this study, we focus on visualizing the flow distribution in the aortic arch, the effect of carotid compression and the influence of compression time and MAP during CPB on reducing cerebral emboli. Experiments are performed with an aortic arch model in a mock cardiovascular system. Fluorescent particles are used to simulate emboli that are released into circulation immediately after carotid compression. The LVAD is used as the pump to produce flow in the system by gradually adjusting the speed to maintain desired clinical conditions. Aortic and proximal branches MAP of 65.0 +/- 5.0 mmHg (normal MAP) or 95.0 +/- 5.0 mmHg (high MAP), aortic flow of 4.0 +/- 0.5 L/min, and all branches flow (left and right carotids, and subclavian arteries) of 10% of the aortic flow. Flow distribution of particles is visualized using LaVision's DaVis imaging software and analyzed using imagej's particle analysis tool to track, count, and record particle properties from the aortic arch. Carotid compression for 10-20 seconds reduces the number of particles entering the carotid arteries by over 73% at normal MAP, and by over 85% at high MAP. A higher MAP resulted in fewer particles entering the branching vessels both at baseline and during occlusion conditions. A compression duration of 20s does not result in greater particle reduction than one of 10s. Our results demonstrate that brief compression of the common carotid arteries during an embolic shower can reduce the number of dangerous emboli by over 85%.

Cardiorespiratory interactions and blood flow generation during cardiac arrest and other states of low blood flow.

PubMed

Sigurdsson, Gardar; Yannopoulos, Demetris; McKnite, Scott H; Lurie, Keith G

2003-06-01

Recent advances in cardiopulmonary resuscitation have shed light on the importance of cardiorespiratory interactions during shock and cardiac arrest. This review focuses on recently published studies that evaluate factors that determine preload during chest compression, methods that can augment preload, and the detrimental effects of hyperventilation and interrupting chest compressions. Refilling of the ventricles, so-called ventricular preload, is diminished during cardiovascular collapse and resuscitation from cardiac arrest. In light of the potential detrimental effects and challenges of large-volume fluid resuscitations, other methods have increasing importance. During cardiac arrest, active decompression of the chest and impedance of inspiratory airflow during the recoil of the chest work by increasing negative intrathoracic pressure and, hence, increase refilling of the ventricles and increase cardiac preload, with improvement in survival. Conversely, increased frequency of ventilation has detrimental effects on coronary perfusion pressure and survival rates in cardiac arrest and severe shock. Prolonged interruption of chest compressions for delivering single-rescuer ventilation or analyzing rhythm before shock delivery is associated with decreased survival rate. Cardiorespiratory interactions are of profound importance in states of cardiovascular collapse in which increased negative intrathoracic pressure during decompression of the chest has a favorable effect and increased intrathoracic pressure with ventilation has a detrimental effect on survival rate.

Left Right Patterning, Evolution and Cardiac Development

PubMed Central

Dykes, Iain M.

2018-01-01

Many aspects of heart development are determined by the left right axis and as a result several congenital diseases have their origins in aberrant left-right patterning. Establishment of this axis occurs early in embryogenesis before formation of the linear heart tube yet impacts upon much later morphogenetic events. In this review I discuss the differing mechanisms by which left-right polarity is achieved in the mouse and chick embryos and comment on the evolution of this system. I then discus three major classes of cardiovascular defect associated with aberrant left-right patterning seen in mouse mutants and human disease. I describe phenotypes associated with the determination of atrial identity and venous connections, looping morphogenesis of the heart tube and finally the asymmetric remodelling of the embryonic branchial arch arterial system to form the leftward looped arch of aorta and associated great arteries. Where appropriate, I consider left right patterning defects from an evolutionary perspective, demonstrating how developmental processes have been modified in species over time and illustrating how comparative embryology can aide in our understanding of congenital heart disease. PMID:29755990

Parasympathetic Stimulation Elicits Cerebral Vasodilatation in Rat

PubMed Central

Talman, William T.; Corr, Julie; Dragon, Deidre Nitschke; Wang, DeQiang

2010-01-01

Forebrain arteries receive nitroxidergic input from parasympathetic ganglionic fibers that arise from the pterygopalatine ganglia. Previous studies have shown that ganglionic stimulation in some species led to cerebral vasodilatation while interruption of those fibers interfered with vasodilatation seen during acute hypertension. Because the ganglionic fibers are quite delicate and are easily damaged when the ganglia are approached with published techniques we sought to develop a method that allowed clear exposure of the ganglia and permitted demonstration of cerebral vasodilatation with electrical stimulation of the ganglia in the rat. We had found that an orbital approach during which the eye was retracted for visualization of the ganglion precluded eliciting vasodilatation with ganglionic stimulation. In the current study approaching the ganglion through an incision over the zygomatic arch provided clear exposure of the ganglion and stimulation of the ganglion with that approach led to vasodilatation. PMID:17275420

The paediatric cardiac centre for Africa--proceedings of the March 2012 symposium.

PubMed

Kinsley, Robin H; Edwin, Frank; Entsua-Mensah, Kow

2013-04-01

The Pediatric Cardiac Centre for Africa (PCCA) was opened by national patron Mr Nelson Mandela on November 7, 2003. In 2008, the Centre's international pediatric cardiac symposium was introduced as a learning forum for pediatric cardiac surgeons and cardiologists in the continent. The symposium has consistently grown in attendance and attracted distinguished leaders in the field. The 2012 symposium featured Dr. Thomas Spray of Children's Hospital of Philadelphia, Dr. David Barron of Birmingham Children's Hospital, and Dr. John Brown of Indiana University School of Medicine as guest speakers. Experience of the Fontan procedure, the small aortic root, hypoplastic left heart syndrome, right ventricular outflow tract reconstruction, transposition of the great arteries, and interrupted aortic arch were the highlights of the symposium. In the "African Corner," centers in South Africa, Ghana, and Angola presented work done from across the African continent.

The value of transthoracic echocardiography in the diagnosis of anomalous origin of the right pulmonary artery from the ascending aorta: A single center experience from China.

PubMed

Wang, Jing; Song, Yue; Cheng, Tsung O; Xie, Mingxing; Wang, Xinfang; Yuan, Li; Yang, Yali; Wang, Lei

2015-04-01

Anomalous origin of pulmonary artery (AOPA) from the ascending aorta is a rare but serious congenital cardiac malformation, which frequently involves the right pulmonary artery (RPA). We retrospectively analyzed the echocardiographic characteristics of 9 cases with anomalous origin of the right pulmonary artery from the ascending aorta (AORPA) studied from 2007 to 2014 in our institution. The results were compared with the findings at surgery. The corrective surgery was performed in all 9 cases with AORPA. The diagnosis by transthoracic echocardiography (TTE) of 8 cases with AORPA was confirmed at surgery. The coincidence rate for TTE and surgical findings was 88.9%. One case was misdiagnosed as anomalous origin of the left pulmonary artery from the ascending aorta. The anomalous RPA in all cases had a proximal origin from the posterior or lateral part of the ascending aorta in our series. The mean distance from the aortic valve to the site of origin of pulmonary artery was 16.1 ± 6.6 mm (range: 7.0 mm-24.0 mm). The mean diameter of the anomalous pulmonary artery was 9.6 ± 4.5 mm (range: 4.5 mm-17.0 mm). In 4 of 9 (44.5%) cases there were associated aortopulmonary septal defect, intact ventricular septum, patent ductus arteriosus and interruption of aortic arch (Type A), also known as the Berry's syndrome. Other associated cardiovascular abnormalities included patent ductus arteriosus, ventricular septal defect and atrial septal defect. Severe pulmonary arterial hypertension was noted in all cases. TTE plays an important role in the non-invasive and accurate diagnosis of AORPA. TTE can clearly display its site of origin and course, as well as other associated malformations and hemodynamic changes. TTE also plays an important role in the preoperative diagnosis of AORPA. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Double aortic arch

MedlinePlus

Aortic arch anomaly; Double arch; Congenital heart defect - double aortic arch; Birth defect heart - double aortic arch ... aorta is a single arch that leaves the heart and moves leftward. In double aortic arch, some ...

Maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width groups

PubMed Central

Shahid, Fazal; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli

2015-01-01

Objective: To investigate the maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width (intercanine, interpremolar, and intermolar) groups. Materials and Methods: The calculated sample size was 128 subjects. The crown width/height, arch length, arch perimeter, and arch width of the maxilla and mandible were obtained via digital calliper (Mitutoyo, Japan). A total of 4325 variables were measured. The sex differences in the crown width and height were evaluated. Analysis of variance was applied to evaluate the differences between arch length, arch perimeter, and arch width groups. Results: Males had significantly larger mean values for crown width and height than females (P ≤ 0.05) for maxillary and mandibular arches, both. There were no significant differences observed for the crown width/height ratio in various arch length, arch perimeter, and arch width (intercanine, interpremolar, and intermolar) groups (P ≤ 0.05) in maxilla and mandible, both. Conclusions: Our results indicate sexual disparities in the crown width and height. Crown width and height has no significant relation to various arch length, arch perimeter, and arch width groups of maxilla and mandible. Thus, it may be helpful for orthodontic and prosthodontic case investigations and comprehensive management. PMID:26929686

[Thyroid hormones and cardiovascular system].

PubMed

Límanová, Zdeňka; Jiskra, Jan

Cardiovascular system is essentially affected by thyroid hormones by way of their genomic and non-genomic effects. Untreated overt thyroid dysfunction is associated with higher cardiovascular risk. Although it has been studied more than 3 decades, in subclinical thyroid dysfunction the negative effect on cardiovascular system is much more controversial. Large meta-analyses within last 10 years have shown that subclinical hyperthyroidism is associated with higher cardiovascular risk than subclinical hypothyroidism. Conversely, in patients of age > 85 years subclinical hypothyroidism was linked with lower mortality. Therefore, subclinical hyperthyroidism should be rather treated in the elderly while subclinical hypothyroidism in the younger patients and the older may be just followed. An important problem on the border of endocrinology and cardiology is amiodarone thyroid dysfunction. Effective and safe treatment is preconditioned by distinguishing of type 1 and type 2 amiodarone induced hyperthyroidism. The type 1 should be treated with methimazol, therapeutic response is prolonged, according to recent knowledge immediate discontinuation of amiodarone is not routinely recommended and patient should be usually prepared to total thyroidectomy, or rather rarely 131I radioiodine ablation may be used if there is appropriate accumulation. In the type 2 there is a promt therapeutic response on glucocorticoids (within 1-2 weeks) with permanent remission or development of hypothyroidism. If it is not used for life-threatening arrhytmias, amiodarone may be discontinuated earlier (after several weeks). Amiodarone induced hypothyroidism is treated with levothyroxine without amiodarone interruption.Key words: amiodarone induced thyroid dysfunction - atrial fibrillation - cardiovascular risk - heart failure - hyperthyroidism - hypothyroidism - thyroid stimulating hormone.

Cross-spectral coherence between geomagnetic disturbance and human cardiovascular variables at non-societal frequencies.

PubMed

Watanabe, Y; Hillman, D C; Otsuka, K; Bingham, C; Breus, T K; Cornélissen, G; Halberg, F

1994-01-01

A 35-year-old cardiologist monitored himself with an automatic ABPM-630 (Colin Electronics) monitor, mostly at 15-minute intervals around-the-clock for three years with a few interruptions. In this subject with a family history of high blood pressure and stroke, a cross-spectral analysis revealed a statistically significant coherence at 27.7 days between systolic and diastolic blood pressure and heart rate vs. the geomagnetic disturbance index, Kp. A lesser peak in coherence was found for systolic blood pressure with Kp at a trial period of 4.16 days (P = 0.046). These results suggest that changes in geomagnetism may influence the human circulation, at least in the presence of familial cardiovascular disease risk, and they may do so at frequencies that have no precise human-made cyclic worldwide match.

Simulation of Structures Exhibiting Instability Under Thermal-Mechanical Transient Loading

DTIC Science & Technology

2015-08-25

4 2.1.4 Application to half- sine arches...shallow arches ....................................................... 9 2.2.2 Half- sine arches... sine arches, parabolic arches and cylindrical panels. 2.1 Arches with Geometric Imperfections The nonlinear equilibrium and buckling equations are

Reliability and Correlation of Static and Dynamic Foot Arch Measurement in a Healthy Pediatric Population.

PubMed

Scholz, Timo; Zech, Astrid; Wegscheider, Karl; Lezius, Susanne; Braumann, Klaus-Michael; Sehner, Susanne; Hollander, Karsten

2017-09-01

Measurement of the medial longitudinal foot arch in children is a controversial topic, as there are many different methods without a definite standard procedure. The purpose of this study was to 1) investigate intraday and interrater reliability regarding dynamic arch index and static arch height, 2) explore the correlation between both arch indices, and 3) examine the variation of the medial longitudinal arch at two different times of the day. Eighty-six children (mean ± SD age, 8.9 ± 1.9 years) participated in the study. Dynamic footprint data were captured with a pedobarographic platform. For static arch measurements, a specially constructed caliper was used to assess heel-to-toe length and dorsum height. A mixed model was established to determine reliability and variation. Reliability was found to be excellent for the static arch height index in sitting (intraday, 0.90; interrater, 0.80) and standing positions (0.88 and 0.85) and for the dynamic arch index (both 1.00). There was poor correlation between static and dynamic assessment of the medial longitudinal arch (standing dynamic arch index, r = -0.138; sitting dynamic arch index, r = -0.070). Static measurements were found to be significantly influenced by the time of day (P < .001), whereas the dynamic arch index was unchanged (P = .845). This study revealed some further important findings. The static arch height index is influenced by gender (P = .004), whereas dynamic arch index is influenced by side (P = .011) and body mass index (P < .001). Dynamic and static foot measurements are reliable for medial longitudinal foot arch assessment in children. The variation of static arch measurements during the day has to be kept in mind. For clinical purposes, static and dynamic arch data should be interpreted separately.

Surgical treatment of interrupted aortic arch associated with ventricular septal defect and patent ductus arteriosus in patients over one year of age.

PubMed

Li, Zhiqiang; Li, Bin; Fan, Xiangming; Su, Junwu; Zhang, Jing; He, Yan; Liu, Yinglong

2014-01-01

Interrupted aortic arch (IAA) is a rare congenital anomaly affecting 1.5% of infants with congenital heart disease. Neonatal repair of IAA is required to avoid irreversible pulmonary vascular lesion. However, in China, patients with IAA associated with ventricular septal defect (VSD) and patent ductus arteriosus (PDA) over one year of age are common. So we investigated the outcome of surgical treatment of IAA with VSD and PDA in patients over one year of age. From January 2009 to December 2012, 19 patients with IAA have undergone complete single-stage repair. The patients' mean age was 4.4 years, ranging 1 to 15 years; and their mean weight was 12.8 kg, ranging 4.2 to 36.0 kg. Fifteen IAA were type A, four were type B. Preoperative cardiac catheterization data were available from all patients. Mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) were measured. The measurements of postoperative pulmonary artery pressure were taken in the operating room at the end of the case. All patients underwent echocardiographic examinations before discharged from the hospital. In addition, cardiac catheterization and echocardiographic examinations were performed during follow-up. Selective brain perfusion through the innominate artery during aortic arch reconstruction was used in all patients. Mean follow-up was (1.6±0.8) years. There were two hospital deaths (2/19, 11%). One patient died of pulmonary hypertension crisis, and another died of postoperative low cardiac output. Five cases had other main postoperative complications but no postoperative neurologic complications. Seventeen survivors were followed up, and there were no late deaths or reoperation. Mean cross-clamp duration was (85±22) minutes and selective brain perfusion duration was (34±11) minutes. Two patients required delayed sternal closure at two days postoperatively. Intensive care unit and hospital stays were (9±8) days and (47±24) days, respectively. Pressure gradients across the anastomosis at most recent follow up were less than 22 mmHg. mPAP regressed significantly from preoperative (62.1±8.1) mmHg to postoperative (37.3±11.3) mmHg (P < 0.001) and (24.2±6.0) mmHg at six months after discharged from the hospital (P < 0.001). The pulmonary vascular resistance also regressed significantly from preoperative (1 501.4±335.7) dyn×s×cm(-5) to (485.0±215.1) dyn×s×cm(-5) at six months after discharged from the hospital (P < 0.001). The majority of the seventeen patients (89%) were in New York Heart Association (NYHA) class I, and 11% remained in NYHA class II. Single-stage repair of patients with IAA, VSD and PDA over one year of age can have good surgical results and functional outcomes. Assessment and treatment of pulmonary artery pressure pre-operatively and postoperatively was crucial. mPAP and pulmonary vascular resistance may have regress significantly compared to preoperative values.

A comparative study of inter-abutment distance of dies made from full arch dual-arch impression trays with those made from full arch stock trays: an in vitro study.

PubMed

Reddy, Jagan Mohan; Prashanti, E; Kumar, G Vinay; Suresh Sajjan, M C; Mathew, Xavier

2009-01-01

The dual-arch impression technique is convenient in that it makes the required maxillary and mandibular impressions, as well as the inter-occlusal record in one procedure. The accuracy of inter-abutment distance in dies fabricated from dual-arch impression technique remains in question because there is little information available in the literature. This study was conducted to evaluate the accuracy of inter-abutment distance in dies obtained from full arch dual-arch trays with those obtained from full arch stock metal trays. The metal dual-arch trays showed better accuracy followed by the plastic dual-arch and stock dentulous trays, respectively, though statistically insignificant. The pouring sequence did not have any effect on the inter-abutment distance statistically, though pouring the non-working side of the dual-arch impression first showed better accuracy.

Comparative study on the mechanical mechanism of confined concrete supporting arches in underground engineering.

PubMed

Lv, Zhijin; Qin, Qian; Jiang, Bei; Luan, Yingcheng; Yu, Hengchang

2018-01-01

In order to solve the supporting problem in underground engineering with high stress, square steel confined concrete (SQCC) supporting method is adopted to enhance the control on surrounding rocks, and the control effect is remarkable. The commonly used cross section shapes of confined concrete arch are square and circular. At present, designers have no consensus on which kind is more proper. To search for the answer, this paper makes an analysis on the mechanical properties of the two shapes of the cross-sections. A full-scale indoor comparative test was carried out on the commonly used straight-wall semi-circular SQCC arch and circular steel confined concrete arch (CCC arch). This test is based on self-developed full-scale test system for confined concrete arch. Our research, combining with the numerical analysis, shows: (1) SQCC arch is consistent with CCC arch in the deformation and failure mode. The largest damages parts are at the legs of both of them. (2) The SQCC arch's bearing capability is 1286.9 kN, and the CCC arch's ultimate bearing capability is 1072.4kN. Thus, the SQCC arch's bearing capability is 1.2 times that of the CCC arch. (3) The arches are subjected to combined compression and bending, bending moment is the main reason for the arch failure. The section moment of inertia of SQCC arch is 1.26 times of that of CCC arch, and the former is better than the latter in bending performance. The ultimate bearing capacity is positively correlated with the size of the moment of inertia. Based on the above research, the engineering suggestions are as follows: (1) To improve the bearing capacity of the arch, the cross-sectional shape of the chamber should be optimized and the arch bearing mode changed accordingly. (2) The key damaged positions, such as the arch leg, should be reinforced, optimizing the state of force on the arch. SQCC arches should be used for supporting in underground engineering, which is under stronger influence of the bending moment and non-uniform load on the supporting arches. The research results could provide a theoretical basis for the design of confined concrete support in underground engineering.

A Salmon Protein Hydrolysate Exerts Lipid-Independent Anti-Atherosclerotic Activity in ApoE-Deficient Mice

PubMed Central

Busnelli, Marco; Bjørndal, Bodil; Holm, Sverre; Brattelid, Trond; Manzini, Stefano; Ganzetti, Giulia S.; Dellera, Federica; Halvorsen, Bente; Aukrust, Pål; Sirtori, Cesare R.; Nordrehaug, Jan E.; Skorve, Jon; Berge, Rolf K.; Chiesa, Giulia

2014-01-01

Fish consumption is considered health beneficial as it decreases cardiovascular disease (CVD)-risk through effects on plasma lipids and inflammation. We investigated a salmon protein hydrolysate (SPH) that is hypothesized to influence lipid metabolism and to have anti-atherosclerotic and anti-inflammatory properties. 24 female apolipoprotein (apo) E−/− mice were divided into two groups and fed a high-fat diet with or without 5% (w/w) SPH for 12 weeks. The atherosclerotic plaque area in aortic sinus and arch, plasma lipid profile, fatty acid composition, hepatic enzyme activities and gene expression were determined. A significantly reduced atherosclerotic plaque area in the aortic arch and aortic sinus was found in the 12 apoE−/− mice fed 5% SPH for 12 weeks compared to the 12 casein-fed control mice. Immunohistochemical characterization of atherosclerotic lesions in aortic sinus displayed no differences in plaque composition between mice fed SPH compared to controls. However, reduced mRNA level of Icam1 in the aortic arch was found. The plasma content of arachidonic acid (C20∶4n-6) and oleic acid (C18∶1n-9) were increased and decreased, respectively. SPH-feeding decreased the plasma concentration of IL-1β, IL-6, TNF-α and GM-CSF, whereas plasma cholesterol and triacylglycerols (TAG) were unchanged, accompanied by unchanged mitochondrial fatty acid oxidation and acyl-CoA:cholesterol acyltransferase (ACAT)-activity. These data show that a 5% (w/w) SPH diet reduces atherosclerosis in apoE−/− mice and attenuate risk factors related to atherosclerotic disorders by acting both at vascular and systemic levels, and not directly related to changes in plasma lipids or fatty acids. PMID:24840793

Numerical analysis of wall shear stress in ascending aorta before tearing in type A aortic dissection.

PubMed

Chi, Qingzhuo; He, Ying; Luan, Yong; Qin, Kairong; Mu, Lizhong

2017-10-01

Although the incidence of many cardiovascular diseases has declined as medical treatments have improved, the prevalence of aortic dissection (AD) has increased. Compared to type B dissections, type A dissections are more severe, and most patients with type A dissections require surgical treatment. The objective of this study was to investigate the relationships between the wall shear stress (WSS) on the aortic endothelium and the frequent tearing positions using computational fluid dynamics. Five type A dissection cases and two normal aortas were included in the study. First, the structures of the aortas before the type A dissection were reconstructed on the basis of the original imaging data. Analyses of flow in the reconstructed premorbid structures reveals that the rupture positions in three of the five cases corresponded to the area of maximum elevated WSS. Moreover, the WSS at the junction of the aortic arch and descending aorta was found to be elevated, which is considered to be related to the locally disturbed helical flow. Meanwhile, the highest WSS in the patients with premorbid AD was found to be almost double that of the control group. Due to the noticeable morphological differences between the AD cases and the control group, the WSSs in the premorbid structures without vasodilation in the ascending part were estimated. The computational results revealed that the WSS was lower in the aorta without vasodilation, but the pressure drop in this situation was higher than that with vasodilation in the ascending aorta. Significant differences were seen between the AD cases and the control group in the angles of the side branches of the aortic arch and its bending degree. Dilation of the ascending aorta and alterations in the branching angles may be the key determinants of a high WSS that leads to type A dissection. Greater tortuosity of the aortic arch leads to stronger helical flow through the distal aortic arch, which may be related to tears in this region. Copyright © 2017 Elsevier Ltd. All rights reserved.

A statistical shape modelling framework to extract 3D shape biomarkers from medical imaging data: assessing arch morphology of repaired coarctation of the aorta.

PubMed

Bruse, Jan L; McLeod, Kristin; Biglino, Giovanni; Ntsinjana, Hopewell N; Capelli, Claudio; Hsia, Tain-Yen; Sermesant, Maxime; Pennec, Xavier; Taylor, Andrew M; Schievano, Silvia

2016-05-31

Medical image analysis in clinical practice is commonly carried out on 2D image data, without fully exploiting the detailed 3D anatomical information that is provided by modern non-invasive medical imaging techniques. In this paper, a statistical shape analysis method is presented, which enables the extraction of 3D anatomical shape features from cardiovascular magnetic resonance (CMR) image data, with no need for manual landmarking. The method was applied to repaired aortic coarctation arches that present complex shapes, with the aim of capturing shape features as biomarkers of potential functional relevance. The method is presented from the user-perspective and is evaluated by comparing results with traditional morphometric measurements. Steps required to set up the statistical shape modelling analyses, from pre-processing of the CMR images to parameter setting and strategies to account for size differences and outliers, are described in detail. The anatomical mean shape of 20 aortic arches post-aortic coarctation repair (CoA) was computed based on surface models reconstructed from CMR data. By analysing transformations that deform the mean shape towards each of the individual patient's anatomy, shape patterns related to differences in body surface area (BSA) and ejection fraction (EF) were extracted. The resulting shape vectors, describing shape features in 3D, were compared with traditionally measured 2D and 3D morphometric parameters. The computed 3D mean shape was close to population mean values of geometric shape descriptors and visually integrated characteristic shape features associated with our population of CoA shapes. After removing size effects due to differences in body surface area (BSA) between patients, distinct 3D shape features of the aortic arch correlated significantly with EF (r = 0.521, p = .022) and were well in agreement with trends as shown by traditional shape descriptors. The suggested method has the potential to discover previously unknown 3D shape biomarkers from medical imaging data. Thus, it could contribute to improving diagnosis and risk stratification in complex cardiac disease.

Mismatch between stiffness in elastic and muscular arteries as a predictor of vascular calcification in dialysis patients.

PubMed

Laucyte-Cibulskiene, Agne; Petraviciute, Modesta; Gudynaite, Migle; Gumbys, Liutauras; Valanciene, Dileta; Galiauskiene, Kristina; Ryliskyte, Ligita; Rimsevicius, Laurynas; Miglinas, Marius; Strupas, Kestutis

2018-04-01

Vascular calcification is one of the risk factors for arterial stiffness in patients with chronic kidney disease. We hypothesized that a mismatch between elastic and muscular arteries, represented as pulse wave velocity (PWV) ratio, could depict the extent of vascular calcification in end-stage renal disease. We also aimed to compare the predictive PWV ratio value to other factors possibly related to vascular calcification in dialysis population. In this cross-sectional study, in 60 chronic dialysis patients without previous cerebrovascular events, cardiovascular disease and events or clinically evident peripheral artery disease (ankle-brachial index >0.9), carotid-femoral and carotid-radial PWV as well as central hemodynamic parameters were measured by applanation tonometry (SphygmoCor). The PWV ratio using carotid-femoral PWV divided by carotid-radial PWV was calculated. Each patient underwent blood tests and chest X-ray for aortic arch calcification scoring. Two experienced radiologists blinded to patient's medical data evaluated chest X-rays (Cohen's kappa coefficient 0.76) and calculated how many sectors were calcified (Ogawa et al. in Hemodial Int 13:301-306, 2009). Differently scored chest X-rays were repeatedly reviewed and a consensus was reached. The study population consisted of 31 (51.7%) males and 29 (48.3%) females, mean age 52.73 ± 13.76 years. Increased risk for aortic arch calcification was associated with higher PWV ratio even after adjustment for age, height, heart rate, ferritin level and C-reactive protein level (OR 2.59E+04, 95% CI 2.43E+01, 2.65E+09, p = 0.021). PWV ratio together with above-mentioned variables could predict the presence of aortic arch calcification with specificity of 93% (95% CI 78, 99%) and sensitivity of 53% (95% CI 34, 72%). The elastic and muscular arteries' stiffness mismatch was strongly associated with the extent of aortic arch calcification in this dialysis population and had better calcification predictive value compared to other demographic, hemodynamic and biochemical markers.

Increased medial longitudinal arch mobility, lower extremity kinematics, and ground reaction forces in high-arched runners.

PubMed

Williams, D S Blaise; Tierney, Robin N; Butler, Robert J

2014-01-01

Runners with high medial longitudinal arch structure demonstrate unique kinematics and kinetics that may lead to running injuries. The mobility of the midfoot as measured by the change in arch height is also suspected to play a role in lower extremity function during running. The effect of arch mobility in high-arched runners is an important factor in prescribing footwear, training, and rehabilitating the running athlete after injury. To examine the effect of medial longitudinal arch mobility on running kinematics, ground reaction forces, and loading rates in high-arched runners. Cross-sectional study. Human movement research laboratory. A total of 104 runners were screened for arch height. Runners were then identified as having high arches if the arch height index was greater than 0.5 SD above the mean. Of the runners with high arches, 11 rigid runners with the lowest arch mobility (R) were compared with 8 mobile runners with the highest arch mobility (M). Arch mobility was determined by calculating the left arch height index in all runners. Three-dimensional motion analysis of running over ground. Rearfoot and tibial angular excursions, eversion-to-tibial internal-rotation ratio, vertical ground reaction forces, and the associated loading rates. Runners with mobile arches exhibited decreased tibial internal-rotation excursion (mobile: 5.6° ± 2.3° versus rigid: 8.0° ± 3.0°), greater eversion-to-tibial internal-rotation ratio (mobile: 2.1 ± 0.8 versus rigid: 1.5 ± 0.5), decreased second peak vertical ground reaction force values (mobile: 2.3 ± 0.2 × body weight versus rigid: 2.4 ± 0.1 × body weight), and decreased vertical loading rate values (mobile: 55.7 ± 14.1 × body weight/s versus rigid: 65.9 ± 11.4 × body weight/s). Based on the results of this study, it appears that runners with high arch structure but differing arch mobility exhibited differences in select lower extremity movement patterns and forces. Future authors should investigate the impact of arch mobility on running-related injuries.

ArchE - An Architecture Design Assistant

DTIC Science & Technology

2007-08-02

Architecture Design Assistant Len Bass August 2, 2007 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the...ArchE - An Architecture Design Assistant 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...X, Module X 3 Author / Presenter, Date if Needed What is ArchE? ArchE is a software architecture design assistant, which: • Takes quality and

Genotype and cardiovascular phenotype correlations with TBX1 in 1,022 velo-cardio- facial/DiGeorge/22q11.2 deletion syndrome patients

PubMed Central

Guo, Tingwei; McGinn, Donna McDonald; Blonska, Anna; Shanske, Alan; Bassett, Anne; Chow, Eva; Bowser, Mark; Sheridan, Molly; Beemer, Frits; Devriendt, Koen; Swillen, Ann; Breckpot, Jeroen; Digilio, M. Cristina; Marino, Bruno; Dallapiccola, Bruno; Carpenter, Courtney; Zheng, Xin; Johnson, Jacob; Chung, Jonathan; Higgins, Anne Marie; Philip, Nicole; Simon, Tony J.; Coleman, Karlene; Heine-Suner, Damian; Rosell, Jordi; Kates, Wendy; Devoto, Marcella; Goldmuntz, Elizabeth; Zackai, Elaine; Wang, Tao; Shprintzen, Robert; Emanuel, Beverly; Morrow, Bernice

2011-01-01

Haploinsufficiency of TBX1, encoding a T-box transcription factor, is largely responsible for the physical malformations in velo-cardio-facial/DiGeorge/22q11.2 deletion syndrome (22q11DS) patients. Cardiovascular malformations in these patients are highly variable, raising the question as to whether DNA variations in the TBX1 locus on the remaining allele of 22q11.2, could be responsible. To test this, a large sample size is needed. The TBX1 gene was sequenced in 360 consecutive 22q11DS patients. Rare and common variations were identified. We did not detect enrichment in rare SNP number in those with or without a congenital heart defect. One exception was that there was increased number of very rare SNPs between those with normal heart anatomy compared to those with right-sided aortic arch or persistent truncus arteriosus, suggesting potentially protective roles in the SNPs for these phenotype enrichment groups. Nine common SNPs (MAF >0.05) were chosen and used to genotype the entire cohort of 1,022 22q11DS subjects. We did not find a correlation between common SNPs or haplotypes and cardiovascular phenotype. This work demonstrates that common DNA variations in TBX1 do not explain variable cardiovascular expression in 22q11DS patients, implicating existence of modifiers in other genes on 22q11.2 or elsewhere in the genome. PMID:21796729

[Clinical effect of removable lingual arch plus auxiliary spring for dental arch expansion].

PubMed

Sun, Feng-yang; Zhang, Yu

2007-04-01

Observe the clinical effect of removable lingual arch plus auxiliary spring for convenient dental (especially mandibular) arch expansion. Seventeen patients with dental arch constriction complicated by mild dental crowding were enrolled in this study, including 9 requiring maxillary arch expansion and 8 necessitating mandibular expansion. The patients were divided to two groups at random for arch expansion with removable lingual arch plus auxiliary spring and with Quad-helix, respectively, and the effect of arch expansion was compared between the two groups. After 8 weeks of arch expansion, the average width of U4-U4 and U5-U5 in removable lingual arch group was enlarged by 2.2 mm and 3.0 mm, and that in Quad-helix group by 2.3 mm and 3.5 mm, respectively, showing no significant differences between the two groups (P>0.05). After 12 weeks of treatment, the average width of L4-L4 and L5-L5 in the former group was enlarged by 2.3 mm and 2.5 mm, respectively, significantly greater than that in the latter group (1.0 mm and 1.2 mm, P<0.05). Removable lingual arch plus auxiliary spring allows significant expansion of the middle segment of the dental arch (bicuspids), and can be more effective than Quad-helix for mandibular arch expansion.

The effect of foot arch on plantar pressure distribution during standing.

PubMed

Periyasamy, R; Anand, Sneh

2013-07-01

The aim of this study was to explore how foot type affects plantar pressure distribution during standing. In this study, 32 healthy subjects voluntarily participated and the subject feet were classified as: normal feet (n = 23), flat feet (n = 14) and high arch feet (n = 27) according to arch index (AI) values obtained from foot pressure intensity image analysis. Foot pressure intensity images were acquired by a pedopowergraph system to obtain a foot pressure distribution parameter-power ratio (PR) during standing in eight different regions of the foot. Contact area and mean PR were analysed in hind foot, mid-foot and fore foot regions. One-way analysis of variance was used to determine statistical differences between groups. The contact area and mean PR value beneath the mid-foot was significantly increased in the low arch foot when compared to the normal arch foot and high arch foot (p < 0.001) in both feet. However, subjects with low-arch feet had significantly higher body mass index (BMI) compared to subjects with high-arch feet (p < 0.05) and subjects with normal arch feet (p < 0.05) in both feet. In addition, subjects with low-arch feet had significant differences in arch index (AI) value as compared to subjects with high-arch feet (p < 0.001) and subjects with normal arch feet (p < 0.05) in both feet. Mean mid-foot PR value were positively (r = 0.54) correlated with increased arch index (AI) value. A significant (p < 0.05) change was obtained in PR value beneath the mid-foot of low arch feet when compared with other groups in both feet. The findings suggest that there is an increased mid-foot PR value in the low arch foot as compared to the normal arch foot and high arch foot during standing. Therefore, individuals with low arch feet could be at high risk for mid-foot collapse and Charcot foot problems, indicating that foot type should be assessed when determining an individual's risk for foot injury.

Motion planning and synchronized control of the dental arch generator of the tooth-arrangement robot.

PubMed

Jiang, Jin-Gang; Zhang, Yong-De

2013-03-01

The traditional, manual method of reproducing the dental arch form is prone to numerous random errors caused by human factors. The purpose of this study was to investigate the automatic acquisition of the dental arch and implement the motion planning and synchronized control of the dental arch generator of the multi-manipulator tooth-arrangement robot for use in full denture manufacture. First, the mathematical model of the dental arch generator was derived. Then the kinematics and control point position of the dental arch generator of the tooth arrangement robot were calculated and motion planning of each control point was analysed. A hardware control scheme is presented, based on the industrial personal computer and control card PC6401. In order to gain single-axis, precise control of the dental arch generator, we studied the control pulse realization of high-resolution timing. Real-time, closed-loop, synchronous control was applied to the dental arch generator. Experimental control of the dental arch generator and preliminary tooth arrangement were gained by using the multi-manipulator tooth-arrangement robotic system. The dental arch generator can automatically generate a dental arch to fit a patient according to the patient's arch parameters. Repeated positioning accuracy is 0.12 mm for the slipways that drive the dental arch generator. The maximum value of single-point error is 1.83 mm, while the arc-width direction (x axis) is -33.29 mm. A novel system that generates the dental arch has been developed. The traditional method of manually determining the dental arch may soon be replaced by a robot to assist in generating a more individual dental arch. The system can be used to fabricate full dentures and bend orthodontic wires. Copyright © 2012 John Wiley & Sons, Ltd.

Frontal plane multi-segment foot kinematics in high- and low-arched females during dynamic loading tasks.

PubMed

Powell, Douglas W; Long, Benjamin; Milner, Clare E; Zhang, Songning

2011-02-01

The functions of the medial longitudinal arch have been the focus of much research in recent years. Several studies have shown kinematic differences between high- and low-arched runners. No literature currently compares the inter-segmental foot motion of high- and low-arched recreational athletes. The purpose of this study was to examine inter-segmental foot motion in the frontal plane during dynamic loading activities in high- and low-arched female athletes. Inter-segmental foot motions were examined in 10 high- and 10 low-arched female recreational athletes. Subjects performed five barefooted trials in each of the following randomized movements: walking, running, downward stepping and landing. Three-dimensional kinematic data were recorded. High-arched athletes had smaller peak ankle eversion angles in walking, running and downward stepping than low-arched athletes. At the rear-midfoot joint high-arched athletes reached peak eversion later in walking and downward stepping than the low-arched athletes. The high-arched athletes had smaller peak mid-forefoot eversion angles in walking, running and downward stepping than the low-arched athletes. The current findings show that differences in foot kinematics between the high- and low-arched athletes were in position and not range of motion within the foot. Copyright © 2010 Elsevier B.V. All rights reserved.

[Dental arch form reverting by four-point method].

PubMed

Pan, Xiao-Gang; Qian, Yu-Fen; Weng, Si-En; Feng, Qi-Ping; Yu, Quan

2008-04-01

To explore a simple method of reverting individual dental arch form template for wire bending. Individual dental arch form was reverted by four-point method. By defining central point of bracket on bilateral lower second premolar and first molar, certain individual dental arch form could be generated. The arch form generating procedure was then be developed to computer software for printing arch form. Four-point method arch form was evaluated by comparing with direct model measurement on linear and angular parameters. The accuracy and reproducibility were assessed by paired t test and concordance correlation coefficient with Medcalc 9.3 software package. The arch form by four-point method was of good accuracy and reproducibility (linear concordance correlation coefficient was 0.9909 and angular concordance correlation coefficient was 0.8419). The dental arch form reverted by four-point method could reproduce the individual dental arch form.

Computational fluid dynamics (CFD) study on the fetal aortic coarctation

NASA Astrophysics Data System (ADS)

Zhou, Yue; Zhang, Yutao; Wang, Jingying

2018-03-01

Blood flows in normal and coarctate fetal aortas are simulated by the CFD technique using T-rex grids. The three-dimensional (3-D) digital model of the fetal arota is reconstructed by the computer-aided design (CAD) software based on two-dimensional (2-D) ultrasono tomographic images. Simulation results displays the development and enhancement of the secondary flow structure in the coarctate fetal arota. As the diameter narrow ratio rises greater than 45%, the pressure and wall shear stress (WSS) of the aorta arch increase exponentially, which is consistent with the conventional clinical concept. The present study also demonstrates that CFD is a very promising assistant technique to investigate human cardiovascular diseases.

Comparative study on the mechanical mechanism of confined concrete supporting arches in underground engineering

PubMed Central

Qin, Qian; Jiang, Bei; Luan, Yingcheng; Yu, Hengchang

2018-01-01

In order to solve the supporting problem in underground engineering with high stress, square steel confined concrete (SQCC) supporting method is adopted to enhance the control on surrounding rocks, and the control effect is remarkable. The commonly used cross section shapes of confined concrete arch are square and circular. At present, designers have no consensus on which kind is more proper. To search for the answer, this paper makes an analysis on the mechanical properties of the two shapes of the cross-sections. A full-scale indoor comparative test was carried out on the commonly used straight-wall semi-circular SQCC arch and circular steel confined concrete arch (CCC arch). This test is based on self-developed full-scale test system for confined concrete arch. Our research, combining with the numerical analysis, shows: (1) SQCC arch is consistent with CCC arch in the deformation and failure mode. The largest damages parts are at the legs of both of them. (2) The SQCC arch’s bearing capability is 1286.9 kN, and the CCC arch’s ultimate bearing capability is 1072.4kN. Thus, the SQCC arch’s bearing capability is 1.2 times that of the CCC arch. (3) The arches are subjected to combined compression and bending, bending moment is the main reason for the arch failure. The section moment of inertia of SQCC arch is 1.26 times of that of CCC arch, and the former is better than the latter in bending performance. The ultimate bearing capacity is positively correlated with the size of the moment of inertia. Based on the above research, the engineering suggestions are as follows: (1) To improve the bearing capacity of the arch, the cross-sectional shape of the chamber should be optimized and the arch bearing mode changed accordingly. (2) The key damaged positions, such as the arch leg, should be reinforced, optimizing the state of force on the arch. SQCC arches should be used for supporting in underground engineering, which is under stronger influence of the bending moment and non-uniform load on the supporting arches. The research results could provide a theoretical basis for the design of confined concrete support in underground engineering. PMID:29447187

Runner's knowledge of their foot type: do they really know?

PubMed

Hohmann, Erik; Reaburn, Peter; Imhoff, Andreas

2012-09-01

The use of correct individually selected running shoes may reduce the incidence of running injuries. However, the runner needs to be aware of their foot anatomy to ensure the "correct" footwear is chosen. The purpose of this study was to compare the individual runner's knowledge of their arch type to the arch index derived from a static footprint. We examined 92 recreational runners with a mean age of 35.4±11.4 (12-63) years. A questionnaire was used to investigate the knowledge of the runners about arch height and overpronation. A clinical examination was undertaken using defined criteria and the arch index was analysed using weight-bearing footprints. Forty-five runners (49%) identified their foot arch correctly. Eighteen of the 41 flat-arched runners (44%) identified their arch correctly. Twenty-four of the 48 normal-arched athletes (50%) identified their arch correctly. Three subjects with a high arch identified their arch correctly. Thirty-eight runners assessed themselves as overpronators; only four (11%) of these athletes were positively identified. Of the 34 athletes who did not categorize themselves as overpronators, four runners (12%) had clinical overpronation. The findings of this research suggest that runners possess poor knowledge of both their foot arch and dynamic pronation. Copyright © 2012 Elsevier Ltd. All rights reserved.

A geometric reappraisal of proximal landing zones for thoracic endovascular aortic repair according to aortic arch types.

PubMed

Marrocco-Trischitta, Massimiliano M; de Beaufort, Hector W; Secchi, Francesco; van Bakel, Theodorus M; Ranucci, Marco; van Herwaarden, Joost A; Moll, Frans L; Trimarchi, Santi

2017-06-01

This study assessed whether the additional use of the aortic arch classification in type I, II, and III may complement Ishimaru's aortic arch map and provide valuable information on the geometry and suitability of proximal landing zones for thoracic endovascular aortic repair. Anonymized thoracic computed tomography scans of healthy aortas were reviewed and stratified according to the aortic arch classification, and 20 of each type of arch were selected. Further processing allowed calculation of angulation and tortuosity of each proximal landing zone. Data were described indicating both proximal landing zone and type of arch (eg, 0/I). Angulation was severe (>60°) in 2/III and in 3/III. Comparisons among the types of arch showed an increase in proximal landing zones angulation (P < .001) and tortuosity (P = .009) depending on the type of arch. Comparisons within type of arch showed no change in angulation and tortuosity across proximal landing zones within type I arch (P = .349 and P = .409), and increases in angulation and tortuosity toward more distal proximal landing zones within type II (P = .003 and P = .043) and type III (P < .001 in both). The aortic arch classification is associated with a consistent geometric pattern of the aortic arch map, which identifies specific proximal landing zones with suboptimal angulation for stent graft deployment. Arches II and III also appear to have progressively less favorable anatomy for thoracic endovascular aortic repair compared with arch I. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

The Foot's Arch and the Energetics of Human Locomotion.

PubMed

Stearne, Sarah M; McDonald, Kirsty A; Alderson, Jacqueline A; North, Ian; Oxnard, Charles E; Rubenson, Jonas

2016-01-19

The energy-sparing spring theory of the foot's arch has become central to interpretations of the foot's mechanical function and evolution. Using a novel insole technique that restricted compression of the foot's longitudinal arch, this study provides the first direct evidence that arch compression/recoil during locomotion contributes to lowering energy cost. Restricting arch compression near maximally (~80%) during moderate-speed (2.7 ms(-1)) level running increased metabolic cost by + 6.0% (p < 0.001, d = 0.67; unaffected by foot strike technique). A simple model shows that the metabolic energy saved by the arch is largely explained by the passive-elastic work it supplies that would otherwise be done by active muscle. Both experimental and model data confirm that it is the end-range of arch compression that dictates the energy-saving role of the arch. Restricting arch compression had no effect on the cost of walking or incline running (3°), commensurate with the smaller role of passive-elastic mechanics in these gaits. These findings substantiate the elastic energy-saving role of the longitudinal arch during running, and suggest that arch supports used in some footwear and orthotics may increase the cost of running.

Evaluation of arch form between Vietnamese and North American Caucasians using 3-dimensional virtual models.

PubMed

Trang, Vu Thi Thu; Park, Jae Hyun; Bayome, Mohamed; Shastry, Shruti; Mellion, Alex; Kook, Yoon-Ah

2015-01-01

The purpose of this study was to investigate the three-dimensional (3D) morphologic differences in the mandibular arch of Vietnamese and North American White subjects. The sample included 113 Vietnamese subjects (41 Class I, 37 Class II and 35 Class III) and 96 White subjects (29 Class I, 30 Class II and 37 Class III). The samples were regrouped according to arch form types (tapered, ovoid, and square) to compare the frequency distribution of the three arch forms between ethnic groups in each angle classification. The facial axis point of each tooth was digitized on 3D virtual models. Four linear and two ratio variables were measured. In comparing arch dimensions, the intercanine and intermolar widths were wider in Vietnamese than in Whites (p < 0.001, p = 0.042, respectively). In the White group, there was even frequency distribution of the three arch forms. However, in the Vietnamese group, the square arch form was the most frequent followed by tapered and ovoid arch forms. The arch forms of Whites were narrower than Vietnamese. In North American Whites, the distribution of the arch form types showed similar frequency. In Vietnamese, the square arch form was more frequent.

The biomechanics of zygomatic arch shape

PubMed Central

Smith, Amanda L.; Grosse, Ian R.

2017-01-01

Mammalian zygomatic arch shape is remarkably variable, ranging from nearly cylindrical to blade-like in cross section. Based on geometry, the arch can be hypothesized to be a sub-structural beam whose ability to resist deformation is related to cross sectional shape. We expect zygomatic arches with different cross sectional shapes to vary in the degree to which they resist local bending and torsion due to the contraction of the masseter muscle. A stiffer arch may lead to an increase in the relative proportion of applied muscle load being transmitted through the arch to other cranial regions, resulting in elevated cranial stress (and thus, strain). Here, we examine the mechanics of the zygomatic arch using a series of finite element modeling experiments in which the cross section of the arch of Pan troglodytes has been modified to conform to idealized shapes (cylindrical, elliptical, blade-like). We find that the shape of the zygomatic arch has local effects on stain that do not conform to beam theory. One exception is that possessing a blade-like arch leads to elevated strains at the postorbital zygomatic junction and just below the orbits. Furthermore, although modeling the arch as solid cortical bone did not have the effect of elevating strains in other parts of the face, as had been expected, it does have a small effect on stress associated with masseter contraction. These results are counterintuitive. Even though the arch has simple beam-like geometry, we fail to find a simple mechanical explanation for the diversity of arch shape. PMID:27870343

Overview of current surgical strategies for aortic disease in patients with Marfan syndrome.

PubMed

Miyahara, Shunsuke; Okita, Yutaka

2016-09-01

Marfan syndrome is a heritable, systemic disorder of the connective tissue with a high penetrance, named after Dr. Antoine Marfan. The most clinically important manifestations of this syndrome are cardiovascular pathologies which cause life-threatening events, such as acute aortic dissections, aortic rupture and regurgitation of the aortic valve or other artrioventricular valves leading to heart failure. These events play important roles in the life expectancy of patients with this disorder, especially prior to the development of effective surgical approaches for proximal ascending aortic disease. To prevent such catastrophic aortic events, a lower threshold has been recommended for prophylactic interventions on the aortic root. After prophylactic root replacement, disease in the aorta beyond the root and distal to the arch remains a cause for concern. Multiple surgeries are required throughout a patient's lifetime that can be problematic due to distal lesions complicated by dissection. Many controversies in surgical strategies remain, such as endovascular repair, to manage such complex cases. This review examines the trends in surgical strategies for the treatment of cardiovascular disease in patients with Marfan syndrome, and current perspectives in this field.

Automated quantitative 3D analysis of aorta size, morphology, and mural calcification distributions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurugol, Sila, E-mail: sila.kurugol@childrens.harvard.edu; Come, Carolyn E.; Diaz, Alejandro A.

Purpose: The purpose of this work is to develop a fully automated pipeline to compute aorta morphology and calcification measures in large cohorts of CT scans that can be used to investigate the potential of these measures as imaging biomarkers of cardiovascular disease. Methods: The first step of the automated pipeline is aorta segmentation. The algorithm the authors propose first detects an initial aorta boundary by exploiting cross-sectional circularity of aorta in axial slices and aortic arch in reformatted oblique slices. This boundary is then refined by a 3D level-set segmentation that evolves the boundary to the location of nearbymore » edges. The authors then detect the aortic calcifications with thresholding and filter out the false positive regions due to nearby high intensity structures based on their anatomical location. The authors extract the centerline and oblique cross sections of the segmented aortas and compute the aorta morphology and calcification measures of the first 2500 subjects from COPDGene study. These measures include volume and number of calcified plaques and measures of vessel morphology such as average cross-sectional area, tortuosity, and arch width. Results: The authors computed the agreement between the algorithm and expert segmentations on 45 CT scans and obtained a closest point mean error of 0.62 ± 0.09 mm and a Dice coefficient of 0.92 ± 0.01. The calcification detection algorithm resulted in an improved true positive detection rate of 0.96 compared to previous work. The measurements of aorta size agreed with the measurements reported in previous work. The initial results showed associations of aorta morphology with calcification and with aging. These results may indicate aorta stiffening and unwrapping with calcification and aging. Conclusions: The authors have developed an objective tool to assess aorta morphology and aortic calcium plaques on CT scans that may be used to provide information about the presence of cardiovascular disease and its clinical impact in smokers.« less

Automated quantitative 3D analysis of aorta size, morphology, and mural calcification distributions.

PubMed

Kurugol, Sila; Come, Carolyn E; Diaz, Alejandro A; Ross, James C; Kinney, Greg L; Black-Shinn, Jennifer L; Hokanson, John E; Budoff, Matthew J; Washko, George R; San Jose Estepar, Raul

2015-09-01

The purpose of this work is to develop a fully automated pipeline to compute aorta morphology and calcification measures in large cohorts of CT scans that can be used to investigate the potential of these measures as imaging biomarkers of cardiovascular disease. The first step of the automated pipeline is aorta segmentation. The algorithm the authors propose first detects an initial aorta boundary by exploiting cross-sectional circularity of aorta in axial slices and aortic arch in reformatted oblique slices. This boundary is then refined by a 3D level-set segmentation that evolves the boundary to the location of nearby edges. The authors then detect the aortic calcifications with thresholding and filter out the false positive regions due to nearby high intensity structures based on their anatomical location. The authors extract the centerline and oblique cross sections of the segmented aortas and compute the aorta morphology and calcification measures of the first 2500 subjects from COPDGene study. These measures include volume and number of calcified plaques and measures of vessel morphology such as average cross-sectional area, tortuosity, and arch width. The authors computed the agreement between the algorithm and expert segmentations on 45 CT scans and obtained a closest point mean error of 0.62 ± 0.09 mm and a Dice coefficient of 0.92 ± 0.01. The calcification detection algorithm resulted in an improved true positive detection rate of 0.96 compared to previous work. The measurements of aorta size agreed with the measurements reported in previous work. The initial results showed associations of aorta morphology with calcification and with aging. These results may indicate aorta stiffening and unwrapping with calcification and aging. The authors have developed an objective tool to assess aorta morphology and aortic calcium plaques on CT scans that may be used to provide information about the presence of cardiovascular disease and its clinical impact in smokers.

Automated quantitative 3D analysis of aorta size, morphology, and mural calcification distributions

PubMed Central

Kurugol, Sila; Come, Carolyn E.; Diaz, Alejandro A.; Ross, James C.; Kinney, Greg L.; Black-Shinn, Jennifer L.; Hokanson, John E.; Budoff, Matthew J.; Washko, George R.; San Jose Estepar, Raul

2015-01-01

Purpose: The purpose of this work is to develop a fully automated pipeline to compute aorta morphology and calcification measures in large cohorts of CT scans that can be used to investigate the potential of these measures as imaging biomarkers of cardiovascular disease. Methods: The first step of the automated pipeline is aorta segmentation. The algorithm the authors propose first detects an initial aorta boundary by exploiting cross-sectional circularity of aorta in axial slices and aortic arch in reformatted oblique slices. This boundary is then refined by a 3D level-set segmentation that evolves the boundary to the location of nearby edges. The authors then detect the aortic calcifications with thresholding and filter out the false positive regions due to nearby high intensity structures based on their anatomical location. The authors extract the centerline and oblique cross sections of the segmented aortas and compute the aorta morphology and calcification measures of the first 2500 subjects from COPDGene study. These measures include volume and number of calcified plaques and measures of vessel morphology such as average cross-sectional area, tortuosity, and arch width. Results: The authors computed the agreement between the algorithm and expert segmentations on 45 CT scans and obtained a closest point mean error of 0.62 ± 0.09 mm and a Dice coefficient of 0.92 ± 0.01. The calcification detection algorithm resulted in an improved true positive detection rate of 0.96 compared to previous work. The measurements of aorta size agreed with the measurements reported in previous work. The initial results showed associations of aorta morphology with calcification and with aging. These results may indicate aorta stiffening and unwrapping with calcification and aging. Conclusions: The authors have developed an objective tool to assess aorta morphology and aortic calcium plaques on CT scans that may be used to provide information about the presence of cardiovascular disease and its clinical impact in smokers. PMID:26328995

Aortic Arch Width and Cardiovascular Disease in Men and Women in the Community.

PubMed

Chuang, Michael L; Gona, Philimon N; Qazi, Saadia; Musgrave, Rebecca M; Fox, Caroline S; Massaro, Joseph M; Hoffmann, Udo; O'Donnell, Christopher J

2018-06-16

We sought to determine whether increased aortic arch width (AAW) adds to standard Framingham risk factors and coronary artery calcium (CAC) for prediction of incident adverse cardiovascular disease (CVD) events in community-dwelling adults. A total of 3026 Framingham Heart Study Offspring and Third Generation cohort participants underwent noncontrast multidetector computed tomography from 2002 to 2005 to quantify CAC. We measured AAW as the distance between the centroids of the ascending and descending thoracic aorta, at the level of main pulmonary artery bifurcation or the right pulmonary artery. We determined sex, age group, and body size specific cut points for high (≥90th percentile) AAW from a healthy referent group (N=1471) and dichotomized AAW as high or not high across all study participants. Clinical covariates were obtained at Offspring cycle 7 (1998-2001) or Third Generation cycle 1 (2002-2005) examinations. The primary CVD outcome was a composite of myocardial infarction, coronary insufficiency, cerebrovascular accident, first hospitalization for heart failure, or CVD death. Cox proportional hazards models were used to estimate hazard ratio of high AAW on time-to-incident CVD after adjustment for Framingham risk factors and CAC. Net reclassification improvement was used to assess the effect of adding AAW to the baseline Framingham risk factor+CAC model. A total of 2826 participants (aged 51±11 years, 48% women) had complete covariates and were free of CVD at multidetector computed tomography. Over a median 8.9 years of follow-up, there were 135 incident CVD events. High AAW was independently predictive of CVD events (hazard ratio, 1.55; P =0.032) and appropriately reclassified participants at risk: net reclassification improvement, 0.31 (95% confidence interval, 0.15-0.48). AAW augments traditional CVD risk factors and CAC for prediction of incident adverse CVD events among community-dwelling adults. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Best surgical option for arch extension of type B aortic dissection: the open approach

PubMed Central

Kim, Joon Bum

2014-01-01

Arch extension of aortic dissection (AD) is reported to occur in 4-25% of patients presenting with acute type B AD. The DeBakey and Stanford classifications do not specifically account for this subset, however, recent studies have demonstrated that the prognosis of patients with arch extension in acute type B AD is virtually identical to that of others with type B AD. In this sense, it seems reasonable to extend the general management principles that are applied to classic acute type B AD even to patients with arch extension. This may be because even in patients with arch extension, most complications occur at locations distal to the arch, and therefore treatment of these patients is similar to that of complicated type B AD, namely thoracic endovascular aortic repair (TEVAR). Conversely, 10% of patients with acute type B AD and arch extension develop complications that are directly related to the arch pathology. This clinical scenario generally necessitates surgical arch repair through a sternotomy approach. The frozen elephant trunk technique combined with arch repair is a very reasonable option to treat this unique clinical entity that involves relatively distal locations of the aortic diseases. Combined arch and descending aorta replacement through thoracotomy is an alternative option particularly when the anatomical features of the target lesions are not suitable for a sternotomy approach or TEVAR. Nonetheless, the reported mortality associated with this approach has been exceedingly high. Hybrid arch repair is another consideration in treating these patients to reduce the treatment-related mortality and morbidity, especially when the arch pathology is limited to the distal part. Nevertheless, the safety and efficacy of this procedure in cases with more extensive arch involvement needs to be assessed in further studies in comparison with other treatment modalities. PMID:25133105

A flap based on the plantar digital artery arch branch to improve appearance of reconstructed fingers: Anatomical and clinical application.

PubMed

Tang, Lin-Feng; Ju, Ji-Hui; Liu, Yue-Fei; Lan, Bo; Hou, Rui-Xing

2018-02-01

To investigate blood supply features of the flap based on the plantar digital artery arch and arch branch artery, and the treatment of outcomes of reconstructed fingers by the plantar digital artery arch branch island flap. Eight fresh foot specimens were employed with red emulsion infusion and microdissection. The vascular organization was observed in the second toe, such as initiation site, the course, and the number of the plantar digital artery arch branch. There were 15 fingers of 13 patients (8 males and 5 females) with finger defects accompanied by toe transfer, using the plantar digital artery arch branch flap inserted in the neck of the second toe to correct the appearance defect caused by a narrow "neck" and a bulbous tip. The intact plantar digital arches were identified in all specimens. The plantar digital artery arch had 5 branches. The range of external diameter of the arch branch was 0.4-0.6 mm. All the plantar digital artery arch branch island flaps and the reconstructed fingers survived. These cases were conducted with a follow-up period for 3-18 months (average, 9 months). All the plantar digital artery arch branch island flaps and reconstructed fingers demonstrated a satisfactory appearance and favorable sense function. The reconstructed finger-tip characteristic was good, with no obvious scar hyperplasia. The range of flexion and extension of reconstructed fingers was favorable as well. The plantar digital artery arch and arch branch artery possess regular vasa vasorum and abundant vascularity. A flap based on the plantar digital artery arch branch is an ideal selection for plastic surgery of reconstructed fingers. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Heritability estimates of dental arch parameters in Lithuanian twins.

PubMed

Švalkauskienė, Vilma; Šmigelskas, Kastytis; Šalomskienė, Loreta; Andriuškevičiūtė, Irena; Šalomskienė, Aurelija; Vasiliauskas, Arūnas; Šidlauskas, Antanas

2015-01-01

The genetic influence on dental arch morphology may be country-specific, thus it is reasonable to check the estimates of genetics across different populations. The purpose of this study was to evaluate the heredity of dental arch morphology in the sample of Lithuanian twins with accurate zygosity determination. The study sample consisted of digital dental models of 40 monozygotic (MZ) and 32 dizygotic (DZ) twin pairs. The estimates of heritability (h(2)) for dental arch breadth and length were calculated. All dental arch breadths and lengths were statistically significantly larger in men than in women. Arch length differences between genders were less expressed than largest breadth differences. In the upper jaw the largest genetic effect was found on the arch breadth between lateral incisors. The heritability of dental arch length demonstrated similar differences between upper and lower jaw with mandible dental arch length being more genetically determined. The largest genetic impact was found on the upper dental arch breadth between lateral incisors. Similar, but lower heritability is inherent for canines and first premolars of the upper jaw and first premolars of the lower jaw. It also can be noted, that arch breadths between posterior teeth show lower heritability estimates than between anterior teeth on both jaws. The dental arch in the upper jaw has more expressed genetic component than in the lower jaw.

Arch index and running biomechanics in children aged 10-14 years.

PubMed

Hollander, Karsten; Stebbins, Julie; Albertsen, Inke Marie; Hamacher, Daniel; Babin, Kornelia; Hacke, Claudia; Zech, Astrid

2018-03-01

While altered foot arch characteristics (high or low) are frequently assumed to influence lower limb biomechanics and are suspected to be a contributing factor for injuries, the association between arch characteristics and lower limb running biomechanics in children is unclear. Therefore, the aim of this study was to investigate the relationship between a dynamically measured arch index and running biomechanics in healthy children. One hundred and one children aged 10-14 years were included in this study and underwent a biomechanical investigation. Plantar distribution (Novel, Emed) was used to determine the dynamic arch index and 3D motion capture (Vicon) to measure running biomechanics. Linear mixed models were established to determine the association between dynamic arch index and foot strike patterns, running kinematics, kinetics and temporal-spatial outcomes. No association was found between dynamic arch index and rate of rearfoot strikes (p = 0.072). Of all secondary outcomes, only the foot progression angle was associated with the dynamic arch index (p = 0.032) with greater external rotation in lower arched children. Overall, we found only few associations between arch characteristics and running biomechanics in children. However, altered foot arch characteristics are of clinical interest. Future studies should focus on detailed foot biomechanics and include clinically diagnosed high and low arched children. Copyright © 2018 Elsevier B.V. All rights reserved.

Scanning ion conductance microscopy: a convergent high-resolution technology for multi-parametric analysis of living cardiovascular cells

PubMed Central

Miragoli, Michele; Moshkov, Alexey; Novak, Pavel; Shevchuk, Andrew; Nikolaev, Viacheslav O.; El-Hamamsy, Ismail; Potter, Claire M. F.; Wright, Peter; Kadir, S.H. Sheikh Abdul; Lyon, Alexander R.; Mitchell, Jane A.; Chester, Adrian H.; Klenerman, David; Lab, Max J.; Korchev, Yuri E.; Harding, Sian E.; Gorelik, Julia

2011-01-01

Cardiovascular diseases are complex pathologies that include alterations of various cell functions at the levels of intact tissue, single cells and subcellular signalling compartments. Conventional techniques to study these processes are extremely divergent and rely on a combination of individual methods, which usually provide spatially and temporally limited information on single parameters of interest. This review describes scanning ion conductance microscopy (SICM) as a novel versatile technique capable of simultaneously reporting various structural and functional parameters at nanometre resolution in living cardiovascular cells at the level of the whole tissue, single cells and at the subcellular level, to investigate the mechanisms of cardiovascular disease. SICM is a multimodal imaging technology that allows concurrent and dynamic analysis of membrane morphology and various functional parameters (cell volume, membrane potentials, cellular contraction, single ion-channel currents and some parameters of intracellular signalling) in intact living cardiovascular cells and tissues with nanometre resolution at different levels of organization (tissue, cellular and subcellular levels). Using this technique, we showed that at the tissue level, cell orientation in the inner and outer aortic arch distinguishes atheroprone and atheroprotected regions. At the cellular level, heart failure leads to a pronounced loss of T-tubules in cardiac myocytes accompanied by a reduction in Z-groove ratio. We also demonstrated the capability of SICM to measure the entire cell volume as an index of cellular hypertrophy. This method can be further combined with fluorescence to simultaneously measure cardiomyocyte contraction and intracellular calcium transients or to map subcellular localization of membrane receptors coupled to cyclic adenosine monophosphate production. The SICM pipette can be used for patch-clamp recordings of membrane potential and single channel currents. In conclusion, SICM provides a highly informative multimodal imaging platform for functional analysis of the mechanisms of cardiovascular diseases, which should facilitate identification of novel therapeutic strategies. PMID:21325316

Diapiric origin of the Blytheville and Pascola arches in the Reelfoot rift, east-central United States: Relation to New Madrid seismicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

McKeown, F.A.; Diehl, S.F.; Glick, E.E.

1990-11-01

Most of the earthquakes in the New Madrid seismic zone correlate spatially with the Blytheville arch and part of the Pascoal arch, which are interpreted to be the same structure. Both arches may have formed by diapirism along the axis of the Reelfoot rift. Seismic, geophysical, and drill-hole data indicate that the rocks in the arches are highly deformed and fractured and have gross lithologic properties that make them weaker than rocks adjacent to the arches. The weaker rocks are inferred to fail seismically more readily than the stronger rocks adjacent to the arches.

The Biomechanics of Zygomatic Arch Shape.

PubMed

Smith, Amanda L; Grosse, Ian R

2016-12-01

Mammalian zygomatic arch shape is remarkably variable, ranging from nearly cylindrical to blade-like in cross section. Based on geometry, the arch can be hypothesized to be a sub-structural beam whose ability to resist deformation is related to cross sectional shape. We expect zygomatic arches with different cross sectional shapes to vary in the degree to which they resist local bending and torsion due to the contraction of the masseter muscle. A stiffer arch may lead to an increase in the relative proportion of applied muscle load being transmitted through the arch to other cranial regions, resulting in elevated cranial stress (and thus, strain). Here, we examine the mechanics of the zygomatic arch using a series of finite element modeling experiments in which the cross section of the arch of Pan troglodytes has been modified to conform to idealized shapes (cylindrical, elliptical, blade-like). We find that the shape of the zygomatic arch has local effects on stain that do not conform to beam theory. One exception is that possessing a blade-like arch leads to elevated strains at the postorbital zygomatic junction and just below the orbits. Furthermore, although modeling the arch as solid cortical bone did not have the effect of elevating strains in other parts of the face, as had been expected, it does have a small effect on stress associated with masseter contraction. These results are counterintuitive. Even though the arch has simple beam-like geometry, we fail to find a simple mechanical explanation for the diversity of arch shape. Anat Rec, 299:1734-1752, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The Foot’s Arch and the Energetics of Human Locomotion

PubMed Central

Stearne, Sarah M.; McDonald, Kirsty A.; Alderson, Jacqueline A.; North, Ian; Oxnard, Charles E.; Rubenson, Jonas

2016-01-01

The energy-sparing spring theory of the foot’s arch has become central to interpretations of the foot’s mechanical function and evolution. Using a novel insole technique that restricted compression of the foot’s longitudinal arch, this study provides the first direct evidence that arch compression/recoil during locomotion contributes to lowering energy cost. Restricting arch compression near maximally (~80%) during moderate-speed (2.7 ms−1) level running increased metabolic cost by + 6.0% (p < 0.001, d = 0.67; unaffected by foot strike technique). A simple model shows that the metabolic energy saved by the arch is largely explained by the passive-elastic work it supplies that would otherwise be done by active muscle. Both experimental and model data confirm that it is the end-range of arch compression that dictates the energy-saving role of the arch. Restricting arch compression had no effect on the cost of walking or incline running (3°), commensurate with the smaller role of passive-elastic mechanics in these gaits. These findings substantiate the elastic energy-saving role of the longitudinal arch during running, and suggest that arch supports used in some footwear and orthotics may increase the cost of running. PMID:26783259

Three-dimensional measurement of foot arch in preschool children

PubMed Central

2012-01-01

Background The prevalence of flexible flatfoot is high among preschool-aged children, but the effects of treatment are inconclusive due to the unclear definitions of normal flatfoot. To date, a universally accepted evaluation method of the foot arch in children has not been completely established. Our aims of this study were to establish a new method to evaluate the foot arch from a three dimensional perspective and to investigate the flexibility of the foot arch among children aged from two to six. Methods A total of 44 children aged from two to six years of age were put into five age groups in this study. The navicular height was measured with one leg standing, and both feet were scanned separately in both sitting and one leg standing positions to compute the foot arch volume. The arch volume index, which represents the ratio of the difference in volume between sitting and one leg standing positions to the volume when sitting was calculated to demonstrate the flexibility of the foot arch. The differences of measured parameters between each aged group were analyzed by one-way ANOVA. Results The arch volumes when sitting and standing were highly correlated with the navicular height. The navicular height ranged from 15.75 to 27 mm, the arch volume when sitting ranged from 6,223 to 11,630 mm3, and the arch volume when standing from 3,111 to 7,848 mm3 from two to six years of age. The arch volume index showed a declining trend as age increased. Conclusion This study is the first to describe the foot arch with volume perspective in preschool-aged children. The foot arch volume was highly correlated with the navicular height. Research results show both navicular height index and arch volume index gradually increase with age from two to six. At the same time the arch also becomes rigid with age from two to six. These results could be applied for clinical evaluation of the foot arch and post-treatment evaluation. PMID:23009315

The "New Deadly Quartet" for cardiovascular disease in the 21st century: obesity, metabolic syndrome, inflammation and climate change: how does statin therapy fit into this equation?

PubMed

Clearfield, Michael; Pearce, Melissa; Nibbe, Yasmin; Crotty, David; Wagner, Alesia

2014-01-01

Despite population-based improvements in cardiovascular risk factors, such as blood pressure, cholesterol and smoking, cardiovascular disease still remains the number-one cause of mortality in the United States. In 1989, Kaplan coined the term "Deadly Quartet" to represent a combination of risk factors that included upper body obesity, glucose intolerance, hypertriglyceridemia and hypertension [Kaplan in Arch Int Med 7:1514-1520, 1989]. In 2002, the third report of the National Cholesterol Education Program Adult Treatment Panel (NCEP-ATP III) essentially added low HDL-C criteria and renamed this the "metabolic syndrome." [The National Cholesterol Education Program (NCEP) in JAMA 285:2486-2497, 2001] However, often forgotten was that a pro-inflammatory state and pro-thrombotic state were also considered components of the syndrome, albeit the panel did not find enough evidence at the time to recommend routine screening for these risk factors [The National Cholesterol Education Program (NCEP) in JAMA 285:2486-2497, 2001]. Now over a decade later, it may be time to reconsider this deadly quartet by reevaluating the roles of obesity and subclinical inflammation as they relate to the metabolic syndrome. To complete this new quartet, the addition of increased exposure to elevated levels of particulate matter in the atmosphere may help elucidate why this cardiovascular pandemic continues, despite our concerted efforts. In this article, we will summarize the evidence, focusing on how statin therapy may further impact this new version of the "deadly quartet".

Differential distribution of the Ca (2+) regulator Pcp4 in the branchial arches is regulated by Hoxa2.

PubMed

Anderson, Megan; Amin, Shilu; Luise, Fabiana; Zeef, Leo; Bobola, Nicoletta

2013-01-01

Branchial arches are externally visible tissue bands in the head region of all vertebrate embryos. Although initially formed from similar components, each arch will give rise to different head and neck structures. In a screen designed to characterize the molecular control of branchial arch identity in mouse, we identified Pcp4 as a second branchial arch-specific molecular signature. We further show that the transcription factor Hoxa2 binds to Pcp4 chromatin and regulates Pcp4 expression in the second arch. Hoxa2 is also sufficient to induce Pcp4 expression in anterior first arch cells, which are Pcp4-negative.

Determining shapes and dimensions of dental arches for the use of straight-wire arches in lingual technique.

PubMed

Kairalla, Silvana Allegrini; Scuzzo, Giuseppe; Triviño, Tarcila; Velasco, Leandro; Lombardo, Luca; Paranhos, Luiz Renato

2014-01-01

This study aims to determine the shape and dimension of dental arches from a lingual perspective, and determine shape and size of a straight archwire used for lingual Orthodontics. The study sample comprised 70 Caucasian Brazilian individuals with normal occlusion and at least four of Andrew's six keys. Maxillary and mandibular dental casts were digitized (3D) and the images were analyzed by Delcam Power SHAPET 2010 software. Landmarks on the lingual surface of teeth were selected and 14 measurements were calculated to determine the shape and size of dental arches. Shapiro-Wilk test determined small arch shape by means of 25th percentile (P25%)--an average percentile for the medium arch; and a large one determined by means of 75th percentile (P75%). T-test revealed differences between males and females in the size of 12 dental arches. The straight-wire arch shape used in the lingual straight wire technique is a parabolic-shaped arch, slightly flattened on its anterior portion. Due to similarity among dental arch sizes shown by males and females, a more simplified diagram chart was designed.

Pennsylvanian history of the Chautauqua Arch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennison, A.P.

1993-03-01

Westward extension of the Ozark Uplift known as the Chautauqua Arch is concealed by a Pennsylvanian cover. This cover provides an insight into its later tectonic history subsequent to its major Late Devonian uplift and truncation. Part of this arch was episodically uplifted during Pennsylvanian time in an area extending west from southwestern Missouri along the Kansas-Oklahoma border to western Montgomery County. Recent stratigraphic mapping in that county indicates moderate Late Desmoinesian to Missourian tectonism. Some strata present on both flanks of the arch are either comparatively thin or missing owing to unconformity truncation or non-deposition. Stratal loss involves themore » Lenapah Limestone, the Hepler and Lost Branch formations, the Cherryvale Shale and the Hertha, Drum, Dewey, Stanton and Wyandotte Limestones. Earlier movements also account for the truncation of Morrowan, Atokan and possibly some Early Desmoinesian beds over the arch. Between tectonic episodes along the arch there were periods of relative tectonic quiescence accompanied by shelf-edge carbonate banks, condensed sequences and siliciclastic sedimentation. West of Montgomery County in Chautauqua County, the widespread Late Pennsylvanian Virgilian outcrops show practically no tectonism. Therefore, the name Chautauqua Arch seems inappropriate for this Pennsylvanian arch, and the name Tri-State Arch is proposed. This arch is bounded on the north by the Cherokee Basin and on the south by the northern rise of the Arkoma Basin. Although this arch is commonly omitted on many tectonic maps, it is a stronger gravity feature than the Bourbon Arch about 50 miles northward. Both tectonic and sedimentary structures have produced much oil and gas entrapment along this arch. For example, an east-west fault south of Independence, aligned with buried Proterozoic hills, has been specially productive.« less

10. DETAIL OF WEST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. DETAIL OF WEST ARCH, FROM ROADWAY, SHOWING ARCH RIB, HANGERS AND GUARDRAIL. VIEW TO SOUTH. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

[Aneurism of the subclavian artery associated with Turner's syndrome].

PubMed

Lacombe, M; Esteva, B; Tillous-Borde, I; Lesèche, G

2004-04-01

Arterial aneurysms associated with Turner's syndrome are rare. We report a case of aneurysm of the left subclavian artery in a 16-year-old girl with Turner's syndrome. This patient was operated on: resection of the aneurysm, suture of the aortic arch and reimplantation of the subclavian artery in the left common carotid were performed. At 3-year follow-up, the evolution is favourable. Cardiovascular anomalies are observed in 50% of subjects with Turner's syndrome. This justifies complementary cardiac investigations in these patients. Congenital malformations (bicuspid aortic valve, aortic coarctation, intracardiac communications, valvular lesions) or acquired anomalies (arterial hypertension, aortic dissection) are frequent. Only one similar case of subclavian artery aneurysm has been reported until now. The risk of rupture justifies the surgical treatment.

Influence of posterior dental arch length on brain activity during chewing in patients with mandibular distal extension removable partial dentures.

PubMed

Shoi, K; Fueki, K; Usui, N; Taira, M; Wakabayashi, N

2014-07-01

It is well known that shortened dental arch decreases masticatory function. However, its potential to change brain activity during mastication is unknown. The present study investigates the effect of a shortened posterior dental arch with mandibular removable partial dentures (RPDs) on brain activity during gum chewing. Eleven subjects with missing mandibular molars (mean age, 66.1 years) on both sides received experimental RPDs with interchangeable artificial molars in a crossover trial design. Brain activity during gum chewing with RPDs containing (full dental arch) and lacking artificial molars (shortened dental arch) was measured using functional magnetic resonance imaging. Additionally, masticatory function was evaluated for each dental arch type. Food comminuting and mixing ability and the perceived chewing ability were significantly lower in subjects with a shortened dental arch than those with a full dental arch (P < 0.05). Brain activation during gum chewing with the full dental arch occurred in the middle frontal gyrus, primary sensorimotor cortex extending to the pre-central gyrus, supplementary motor area, putamen, insula and cerebellum. However, middle frontal gyrus activation was not observed during gum chewing with the shortened dental arch. These results suggest that shortened dental arch affects human brain activity in the middle frontal gyrus during gum chewing, and the decreased middle frontal gyrus activation may be associated with decreased masticatory function. © 2014 John Wiley & Sons Ltd.

9. DETAIL OF EAST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. DETAIL OF EAST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ARTICULATED HANGER AND GUARDRAIL. VIEW TO SOUTHEAST. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

Properties of coronal arches

NASA Technical Reports Server (NTRS)

Davis, J. M.; Krieger, A. S.

1982-01-01

The properties of coronal arches located on the peripheries of active regions, observed during a sounding rocket flight on March 8, 1973, are discussed. The arches are found to overlie filament channels and their footpoints are traced on locations on the perimeters of supergranulation cells. The arches have a wide range of lengths although their widths are well approximated by the value 2.2 x 10 to the 9th cm. Comparison of the size of the chromospheric footprint with the arc width indicates that arches do not always expand as they ascend into the corona. The electron temperatures and densities of the plasma contained in the arches were measured and the pressure calculated; typical values are 2-million K, 1 x 10 to the 9th/cu cm, and 0.2 dyne/sq cm, respectively. The variation of these parameters with position along the length of the arch indicates that the arches are not in hydrostatic equilibrium.

In-plane free vibration analysis of cable arch structure

NASA Astrophysics Data System (ADS)

Zhao, Yueyu; Kang, Houjun

2008-05-01

Cable-stayed arch bridge is a new type of composite bridge, which utilizes the mechanical characters of cable and arch. Based on the supporting members of cable-stayed arch bridge and of erection of arch bridge using of the cantilever construction method with tiebacks, we propose a novel mechanical model of cable-arch structure. In this model, the equations governing vibrations of the cable-arch are derived according to Hamilton's principle for dynamic problems in elastic body under equilibrium state. Then, the program of solving the dynamic governing equations is ultimately established by the transfer matrix method for free vibration of uniform and variable cross-section, and the internal characteristics of the cable-arch are investigated. After analyzing step by step, the research results approve that the program is accurate; meanwhile, the mechanical model and method are both valuable and significant not only in theoretical research and calculation but also in design of engineering.

Standardizing Foot-Type Classification Using Arch Index Values

PubMed Central

Weil, Rich; de Boer, Emily

2012-01-01

ABSTRACT Purpose: The lack of a reliable classification standard for foot type makes drawing conclusions from existing research and clinical decisions difficult, since different foot types may move and respond to treatment differently. The purpose of this study was to determine interrater agreement for foot-type classification based on photo-box-derived arch index values. Method: For this correlational study with two raters, a sample of 11 healthy volunteers with normal to obese body mass indices was recruited from both a community weight-loss programme and a programme in physical therapy. Arch index was calculated using AutoCAD software from footprint photographs obtained via mirrored photo-box. Classification as high-arched, normal, or low-arched foot type was based on arch index values. Reliability of the arch index was determined with intra-class correlations; agreement on foot-type classification was determined using quadratic weighted kappa (κw). Results: Average arch index was 0.215 for one tester and 0.219 for the second tester, with an overall range of 0.017 to 0.370. Both testers classified 6 feet as low-arched, 9 feet as normal, and 7 feet as high-arched. Interrater reliability for the arch index was ICC=0.90; interrater agreement for foot-type classification was κw=0.923. Conclusions: Classification of foot type based on arch index values derived from plantar footprint photographs obtained via mirrored photo-box showed excellent reliability in people with varying BMI. Foot-type classification may help clinicians and researchers subdivide sample populations to better differentiate mobility, gait, or treatment effects among foot types. PMID:23729964

Branchial cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings.

PubMed

Adams, Ashok; Mankad, Kshitij; Offiah, Curtis; Childs, Lucy

2016-02-01

The branchial arches are the embryological precursors of the face, neck and pharynx. Anomalies of the branchial arches are the second most common congenital lesions of the head and neck in children, with second branchial arch anomalies by far the most common. Clinically, these congenital anomalies may present as cysts, sinus tracts, fistulae or cartilaginous remnants with typical clinical and radiological findings. We review the normal embryological development of the branchial arches and the anatomical structures of the head and neck that derive from each arch. The typical clinical and radiological appearances of both common and uncommon branchial arch abnormalities are discussed with an emphasis on branchial cleft anomalies. • Anomalies of the branchial arches usually present as cysts, sinuses or fistulae. • Second branchial arch anomalies account for approximately 95 % of cases. • There are no pathognomonic imaging features so diagnosis depends on a high index of suspicion and knowledge of typical locations. • Persistent cysts, fistulae or recurrent localised infection may be due to branchial arch anomalies. • Surgical excision of the cyst or tract is the most common curative option.

3. View locking east of 591 foot steel arch of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. View locking east of 591 foot steel arch of bridge. Arch consists of Pratt trusses divided into twenty-four, 24 foot, 7 inch panels. It was fabricated by the King Iron Bridge Company of Cleveland whose circular plaque can be seen where the arch meets the roadway. The steel arch was erected by the Berro construction Co. of Chicago. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

Impact of statin related media coverage on use of statins: interrupted time series analysis with UK primary care data.

PubMed

Matthews, Anthony; Herrett, Emily; Gasparrini, Antonio; Van Staa, Tjeerd; Goldacre, Ben; Smeeth, Liam; Bhaskaran, Krishnan

2016-06-28

 To quantify how a period of intense media coverage of controversy over the risk:benefit balance of statins affected their use.  Interrupted time series analysis of prospectively collected electronic data from primary care.  Clinical Practice Research Datalink (CPRD) in the United Kingdom.  Patients newly eligible for or currently taking statins for primary and secondary cardiovascular disease prevention in each month in January 2011-March 2015.  Adjusted odds ratios for starting/stopping taking statins after the media coverage (October 2013-March 2014).  There was no evidence that the period of high media coverage was associated with changes in statin initiation among patients with a high recorded risk score for cardiovascular disease (primary prevention) or a recent cardiovascular event (secondary prevention) (odds ratio 0.99 (95% confidence interval 0.87 to 1.13; P=0.92) and 1.04 (0.92 to 1.18; P=0.54), respectively), though there was a decrease in the overall proportion of patients with a recorded risk score. Patients already taking statins were more likely to stop taking them for both primary and secondary prevention after the high media coverage period (1.11 (1.05 to 1.18; P<0.001) and 1.12 (1.04 to 1.21; P=0.003), respectively). Stratified analyses showed that older patients and those with a longer continuous prescription were more likely to stop taking statins after the media coverage. In post hoc analyses, the increased rates of cessation were no longer observed after six months.  A period of intense public discussion over the risks:benefit balance of statins, covered widely in the media, was followed by a transient rise in the proportion of people who stopped taking statins. This research highlights the potential for widely covered health stories in the lay media to impact on healthcare related behaviour. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Dental arch dimensions, form and tooth size ratio among a Saudi sample.

PubMed

Omar, Haidi; Alhajrasi, Manar; Felemban, Nayef; Hassan, Ali

2018-01-01

To determine the dental arch dimensions and arch forms in a sample of Saudi orthodontic patients, to investigate the prevalence of Bolton anterior and overall tooth size discrepancies, and to compare the effect of gender on the measured parameters. Methods: This study is a biometric analysis of dental casts of 149 young adults recruited from different orthodontic centers in Jeddah, Saudi Arabia. The dental arch dimensions were measured. The measured parameters were arch length, arch width, Bolton's ratio, and arch form. The data were analyzed using IBM SPSS software version 22.0 (IBM Corporation, New York, USA); this cross-sectional study was conducted between April 2015 and May 2016. Results: Dental arch measurements, including inter-canine and inter-molar distance, were found to be significantly greater in males than females (p less than 0.05). The most prevalent dental arch forms were narrow tapered (50.3%) and narrow ovoid (34.2%), respectively. The prevalence of tooth size discrepancy in all cases was 43.6% for anterior ratio and 24.8% for overall ratio. The mean Bolton's anterior ratio in all malocclusion classes was 79.81%, whereas the mean Bolton's overall ratio was 92.21%. There was no significant difference between males and females regarding Bolton's ratio. Conclusion: The most prevalent arch form was narrow tapered, followed by narrow ovoid. Males generally had larger dental arch measurements than females, and the prevalence of tooth size discrepancy was more in Bolton's anterior teeth ratio than in overall ratio.

Rearfoot eversion has indirect effects on plantar fascia tension by changing the amount of arch collapse.

PubMed

Lee, Sae Yong; Hertel, Jay; Lee, Sung Cheol

2010-01-01

Rearfoot eversion motion and arch height are believed to contribute to increased tension on the plantar fascia and arch collapse during gait but the specifics of these relationships are not clear. To examine the relationships among static arch height, rearfoot eversion, dynamic arch height, and plantar fascia tension. 28 healthy males participated. After static arch height was measured, the subjects were asked to run at 4.5m/s while frontal plane rearfoot motion, dynamic arch height, and ground reaction forces were collected. The relationships among variables were examined with bivariate correlations and path analysis. The results indicated a high correlation between dynamic arch height and static arch height (r=0.642), plantar fascia tension (r=-0.797), and maximum rearfoot eversion motion during gait (r=-0.518). The path analysis model without the direct rearfoot eversion effect explained 81.2% of the variance in plantar fascia tension, while the model with the direct rearfoot eversion effect explained 82.1% of the variance in plantar fascia tension. Including the indirect effect of maximum rearfoot eversion motion on plantar fascia tension through control of dynamic arch height is the model that best explains the interrelationships of these foot characteristics. The amount of maximum rearfoot eversion motion itself is not a good predictor of plantar fascia tension, however, together with the arch height, maximum rearfoot eversion motion is a good predictor because it has a pronounced indirect effect on plantar fascia tension. Copyright 2010. Published by Elsevier Ltd.

[Angiographic evaluation of branching pattern and anatomy of the aortic arch].

PubMed

Ergun, Onur; Tatar, İdil Güneş; Birgi, Erdem; Durmaz, Hasan Ali; Akçalar, Seray; Kurt, Aydın; Hekimoğlu, Baki

2015-04-01

The study aimed to investigate anatomical variations in branching pattern and anatomy of the aortic arch, and the prevalence of each type. Between September 2011 and November 2013, angiographic studies of 270 patients (144 male, 126 female) were analyzed retrospectively for variations in branching pattern and anatomy of the aortic arch. Patient mean age was 59.8 years (range, 13-88). Branching variations were found and divided into subtypes. Patients were also classified according to arch anatomy. Incidence of variations and types of aortic arch were statistically analysed. Analysis of the 270 patients revealed six types of branching pattern. Type I, classical pattern arch with three branches (TB, LCC, LS), was observed in 198 cases (73.3%). Type II (bovine arch), the most commonly observed variation, in which LCC originates from TB, was observed in 58 cases (21.5%). Type III, in which the left vertebral artery arises from the arch, was seen in seven cases (2.6%). Type IV, a combination of types II and III, was observed in three cases (1.1%). Type V, common origin of common carotids, LS and aberrant RS, was found in three cases (1.1%). Type VI (avian type), arch with only two branches, was observed in one case (0.4%). When patients were classified according to aortic arch anatomy, Type 1, Type 2 and Type 3 were observed in 195, 40 and 35 patients respectively. Knowledge of the variations and anatomy of the aortic arch is essential during interventional procedures and neck-thorax surgery.

Comparison of arch forms between Egyptian and North American white populations.

PubMed

Bayome, Mohamed; Sameshima, Glenn T; Kim, Yoonji; Nojima, Kunihiko; Baek, Seung-Hak; Kook, Yoon-Ah

2011-03-01

The aim of this study was to evaluate the morphologic differences in the mandibular arches of Egyptian and North American white subjects. The sample included 94 Egyptian subjects (35 Class I, 32 Class II, and 27 Class III) and 92 white subjects (37 Class I, 29 Class II, and 26 Class III). The subjects were grouped according to arch form types (tapered, ovoid, and square) to compare their frequency distribution between ethnic groups in each Angle classification. The most facial portions of 13 proximal contact areas were digitized on scanned images of mandibular casts to estimate the corresponding clinical bracket point for each tooth. Four linear and 2 proportional measurements were taken. In comparing arch dimensions, intermolar width was narrower in Egyptians than in the whites (P = 0.001). There was an even frequency distribution of the 3 arch forms in the Egyptian group. On the other hand, the most frequent arch form was ovoid followed by tapered and square in the white group; the square arch form was significantly less frequent than the tapered and ovoid arch forms (P = 0.029). The arch forms of Egyptians are narrower than those of whites. The distribution of the arch form types in Egyptians showed similar frequency, but the square arch form was less frequent in whites. It is recommended to select narrower archwires from the available variations to suit many Egyptian patients. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Improving cardiac operating room to intensive care unit handover using a standardised handover process.

PubMed

Gleicher, Yehoshua; Mosko, Jeffrey David; McGhee, Irene

2017-01-01

Handovers from the cardiovascular operating room (CVOR) to the cardiovascular intensive care unit (CVICU) are complex processes involving the transfer of information, equipment and responsibility, at a time when the patient is most vulnerable. This transfer is typically variable in structure, content and execution. This variability can lead to the omission and miscommunication of critical information leading to patient harm. We set out to improve the quality of patient handover from the CVOR to the CVICU by introducing a standardised handover protocol. This study is an interventional time-series study over a 4-month period at an adult cardiac surgery centre. A standardised handover protocol was developed using quality improvement methodologies. The protocol included a handover content checklist and introduction of a formal 'sterile cockpit' timeout. Implementation of the protocol was refined using monthly iterative Plan-Do-Study-Act. The primary outcome was the quality of handovers, measured by a Handover Score, comprising handover content, teamwork and patient care planning indicators. Secondary outcomes included handover duration, adherence to the standardised handover protocol and handover team satisfaction surveys. 37 handovers were observed (6 pre intervention and 31 post intervention). The mean handover score increased from 6.5 to 14.0 (maximum 18 points). Specific improvements included fewer handover interruptions and more frequent postoperative patient care planning. Average handover duration increased slightly from 2:40 to 2:57 min. Caregivers noted improvements in teamwork, content received and patient care planning. The majority (>95%) agreed that the intervention was a valuable addition to the CVOR to CVICU handover process. Implementation of a standardised handover protocol for postcardiac surgery patients was associated with fewer interruptions during handover, more reliable transfer of critical content and improved patient care planning.

3. VIEW OF DOWNSTREAM ARCHES. MASONRY ABOVE ARCHES IN THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. VIEW OF DOWNSTREAM ARCHES. MASONRY ABOVE ARCHES IN THE SPANDREL WALL IS LAID IN A SEMI-COURSED RUBBLE PATTERN. - Core Creek County Bridge, Spanning Core Creek, approximately 1 mile South of State Route 332 (Newtown Bypass), Newtown, Bucks County, PA

Vocal cord paralysis after aortic arch surgery: predictors and clinical outcome.

PubMed

Ohta, Noriyuki; Kuratani, Toru; Hagihira, Satoshi; Kazumi, Ken-Ichiro; Kaneko, Mitsunori; Mori, Takahiko

2006-04-01

This study is retrospective cohort study of data on vocal cord paralysis after aortic arch surgery collected during 14 years at a general hospital. We investigated factors in the development of vocal cord paralysis after aortic arch surgery and the effect of vocal cord paralysis on clinical course and outcome. We reviewed data for 182 patients who underwent aortic arch surgery for aortic arch aneurysm and aortic dissection between 1989 and 2003, of whom 58 patients had proximal aortic repair, 62 had distal arch repair, and 62 had total arch repair. We assessed factors associated with the development of vocal cord paralysis and examined in detail the clinical outcome of patients with vocal cord paralysis. Postoperative vocal cord paralysis occurred in 40 patients. Multiple logistic regression analysis revealed the following risk factors with odds ratios (OR) for vocal cord paralysis: extension of procedures into distal arch (OR, 17.0), chronic dilatation of the aorta at the left subclavian artery (OR, 9.14), and total arch repair (OR, 4.24). Adoption of open-style stent-grafts reduced the incidence of vocal cord paralysis (OR, 0.031). The postoperative occurrence of vocal cord paralysis itself emerges as an independent predictor of pulmonary complications (OR, 4.12) and leads to a longer duration of hospital stay. The risk of vocal cord paralysis after aortic arch surgery depends on surgical factors, such as aneurysmal involvement of the distal arch, or the application of newer, less invasive surgical procedures. Vocal cord paralysis after aortic arch surgery itself, under aggressive postoperative respiratory management, did not increase aspiration pneumonia but was associated with postoperative complications leading to higher hospital mortality and prolonged hospitalization.

Calcification at orifices of aortic arch branches is a reliable and significant marker of stenosis at carotid bifurcation and intracranial arteries.

PubMed

Yamada, Shigeki; Hashimoto, Kenji; Ogata, Hideki; Watanabe, Yoshihiko; Oshima, Marie; Miyake, Hidenori

2014-02-01

Simple rating scale for calcification in the cervical arteries and the aortic arch on multi-detector computed tomography angiography (MDCTA) was evaluated its reliability and validity. Additionally, we investigated where is the most representative location for evaluating the calcification risk of carotid bifurcation stenosis and atherosclerotic infarction in the overall cervical arteries covering from the aortic arch to the carotid bifurcation. The aortic arch and cervical arteries among 518 patients (292 men, 226 women) were evaluated the extent of calcification using a 4-point grading scale for MDCTA. Reliability, validity and the concomitant risk with vascular stenosis and atherosclerotic infarction were assessed. Calcification was most frequently observed in the aortic arch itself, the orifices from the aortic arch, and the carotid bifurcation. Compared with the bilateral carotid bifurcations, the aortic arch itself had a stronger inter-observer agreement for the calcification score (Fleiss' kappa coefficients; 0.77), but weaker associations with stenosis and atherosclerotic infarction. Calcification at the orifices of the aortic arch branches had a stronger inter-observer agreement (0.74) and enough associations with carotid bifurcation stenosis and intracranial stenosis. In addition, the extensive calcification at the orifices from the aortic arch was significantly associated with atherosclerotic infarction, similar to the calcification at the bilateral carotid bifurcations. The orifices of the aortic arch branches were the novel representative location of the aortic arch and overall cervical arteries for evaluating the calcification extent. Thus, calcification at the aortic arch should be evaluated with focus on the orifices of 3 main branches. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Maxillary arch dimensions associated with acoustic parameters in prepubertal children.

PubMed

Hamdan, Abdul-Latif; Khandakji, Mohannad; Macari, Anthony Tannous

2018-04-18

To evaluate the association between maxillary arch dimensions and fundamental frequency and formants of voice in prepubertal subjects. Thirty-five consecutive prepubertal patients seeking orthodontic treatment were recruited (mean age = 11.41 ± 1.46 years; range, 8 to 13.7 years). Participants with a history of respiratory infection, laryngeal manipulation, dysphonia, congenital facial malformations, or history of orthodontic treatment were excluded. Dental measurements included maxillary arch length, perimeter, depth, and width. Voice parameters comprising fundamental frequency (f0_sustained), Habitual pitch (f0_count), Jitter, Shimmer, and different formant frequencies (F1, F2, F3, and F4) were measured using acoustic analysis prior to initiation of any orthodontic treatment. Pearson's correlation coefficients were used to measure the strength of associations between different dental and voice parameters. Multiple linear regressions were computed for the predictions of different dental measurements. Arch width and arch depth had moderate significant negative correlations with f0 ( r = -0.52; P = .001 and r = -0.39; P = .022, respectively) and with habitual frequency ( r = -0.51; P = .0014 and r = -0.34; P = .04, respectively). Arch depth and arch length were significantly correlated with formant F3 and formant F4, respectively. Predictors of arch depth included frequencies of F3 vowels, with a significant regression equation ( P-value < .001; R 2 = 0.49). Similarly, fundamental frequency f0 and frequencies of formant F3 vowels were predictors of arch width, with a significant regression equation ( P-value < .001; R 2 = 0.37). There is a significant association between arch dimensions, particularly arch length and depth, and voice parameters. The formant most predictive of arch depth and width is the third formant, along with fundamental frequency of voice.

Using ArchE in the Classroom: One Experience

DTIC Science & Technology

2007-09-01

The Architecture Expert (ArchE) tool serves as a software architecture design assistant. It embodies knowledge of quality attributes and the relation...between the achievement of quality attribute requirements and architecture design . This technical note describes the use of a pre-alpha release of

Relationship between lumbar changes and modifications in the plantar arch in women with low back pain.

PubMed

Borges, Cláudia Dos Santos; Fernandes, Luciane Fernanda Rodrigues Martinho; Bertoncello, Dernival

2013-05-01

: Evaluate the probable relationship among plantar arch, lumbar curvature, and low back pain. : Fifteen healthy women were assessed taking in account personal data and anthropometric measurements, photopodoscopic evaluation of the plantar arch, and biophotogrammetric postural analysis of the patient (both using the SAPO software), as well as evaluation of lumbar pain using a Visual Analog Scale (VAS). The average age of the participants was 30.45 (±6.25) years. : Of the feet evaluated, there were six individuals with flat feet, five with high arch, and four with normal feet. All reported algic syndrome in the lumbar spine, with the highest VAS values for the volunteers with high arch. Correlation was observed between the plantar arch and the angle of the lumbar spine (r = -0.71, p = 0.004) CONCLUSION: High arch was correlated with more intense algic syndrome, while there was moderate positive correlation between flat foot and increased lumbar curvature, and between high arch and lumbar correction. Level of Evidence IV. Case Series .

Presentation of obstructive left heart malformations in infancy.

PubMed Central

Abu-Harb, M; Wyllie, J; Hey, E; Richmond, S; Wren, C

1994-01-01

This study documents the presentation of acutely life threatening congenital heart disease in infancy in order to assess the performance of screening examinations soon after birth and at 6 weeks of age. All cases of obstructive left heart malformations presenting in infancy in one health region from 1987-91 were analysed retrospectively. Altogether, 120 infants presented with either hypoplastic left heart syndrome, interruption of the aortic arch, coarctation of the aorta, or aortic valve stenosis. Twelve became symptomatic or died within 24 hours. Thirty four had an abnormal neonatal examination, eight of whom were referred. Six more became symptomatic before discharge. Ninety four babies went home, 51 developed heart failure before 6 weeks, and another seven died without diagnosis. Twenty five of 36 (69%) reaching 6 weeks without diagnosis had a second examination which was abnormal in 17. Two babies died undiagnosed after 6 weeks and the other 18 presented at up to 11 months of age. The neonatal and 6 week examinations perform poorly as screening tests for congenital heart disease. A normal neonatal examination does not exclude life threatening congenital heart disease. Images PMID:7820713

Recurrent Circuitry for Balancing Sleep Need and Sleep.

PubMed

Donlea, Jeffrey M; Pimentel, Diogo; Talbot, Clifford B; Kempf, Anissa; Omoto, Jaison J; Hartenstein, Volker; Miesenböck, Gero

2018-01-17

Sleep-promoting neurons in the dorsal fan-shaped body (dFB) of Drosophila are integral to sleep homeostasis, but how these cells impose sleep on the organism is unknown. We report that dFB neurons communicate via inhibitory transmitters, including allatostatin-A (AstA), with interneurons connecting the superior arch with the ellipsoid body of the central complex. These "helicon cells" express the galanin receptor homolog AstA-R1, respond to visual input, gate locomotion, and are inhibited by AstA, suggesting that dFB neurons promote rest by suppressing visually guided movement. Sleep changes caused by enhanced or diminished allatostatinergic transmission from dFB neurons and by inhibition or optogenetic stimulation of helicon cells support this notion. Helicon cells provide excitation to R2 neurons of the ellipsoid body, whose activity-dependent plasticity signals rising sleep pressure to the dFB. By virtue of this autoregulatory loop, dFB-mediated inhibition interrupts processes that incur a sleep debt, allowing restorative sleep to rebalance the books. VIDEO ABSTRACT. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Hypercarbic cardiorespiratory reflexes in the facultative air-breathing fish jeju (Hoplerythrinus unitaeniatus): the role of branchial CO2 chemoreceptors.

PubMed

de Lima Boijink, Cheila; Florindo, Luiz Henrique; Leite, Cleo A Costa; Kalinin, Ana Lúcia; Milsom, William K; Rantin, Francisco Tadeu

2010-08-15

The aim of the present study was to determine the roles that externally versus internally oriented CO(2)/H(+)-sensitive chemoreceptors might play in promoting cardiorespiratory responses to environmental hypercarbia in the air-breathing fish, Hoplerythrinus unitaeniatus (jeju). Fish were exposed to graded hypercarbia (1, 2.5, 5, 10 and 20% CO(2)) and also to graded levels of environmental acidosis (pH approximately 7.0, 6.0, 5.8, 5.6, 5.3 and 4.7) equal to the pH levels of the hypercarbic water to distinguish the relative roles of CO(2) versus H(+). We also injected boluses of CO(2)-equilibrated solutions (5, 10 and 20% CO(2)) and acid solutions equilibrated to the same pH as the CO(2) boluses into the caudal vein (internal) and buccal cavity (external) to distinguish between internal and external stimuli. The putative location of the chemoreceptors was determined by bilateral denervation of branches of cranial nerves IX (glossopharyngeal) and X (vagus) to the gills. The data indicate that the chemoreceptors eliciting bradycardia, hypertension and gill ventilatory responses (increased frequency and amplitude) to hypercarbia are exclusively branchial, externally oriented and respond specifically to changes in CO(2) and not H(+). Those involved in producing the cardiovascular responses appeared to be distributed across all gill arches while those involved in the gill ventilatory responses were located primarily on the first gill arch. Higher levels of aquatic CO(2) depressed gill ventilation and stimulated air breathing. The chemoreceptors involved in producing air breathing in response to hypercarbia also appeared to be branchial, distributed across all gill arches and responded specifically to changes in aquatic CO(2). This would suggest that chemoreceptor groups with different orientations (blood versus water) are involved in eliciting air-breathing responses to hypercarbia in jeju.

A case of complete double aortic arch visualized by transthoracic echocardiography.

PubMed

Saito, Naka; Kato, Shingo; Saito, Noritaka; Nakachi, Tatsuya; Fukui, Kazuki; Iwasawa, Tae; Kosuge, Masami; Kimura, Kazuo

2017-08-01

A case of double aortic arch that was well visualized using transthoracic echocardiography is reported. A 38-year-old man underwent transthoracic echocardiography for the evaluation of dyspnea. A suprasternal view of transthoracic echocardiography showed the ascending aorta bifurcate to left and right aortic arches, with blood flow from the ascending aorta to bilateral aortic arches. The diagnosis of right side-dominant double aortic arch was made, and the patient's symptom was conceivably related to compression of the trachea due to a vascular ring. This report indicates the potential usefulness of transthoracic echocardiography for noninvasive detection of double aortic arch in adults. © 2017, Wiley Periodicals, Inc.

Automatic segmentation of thoracic aorta segments in low-dose chest CT

NASA Astrophysics Data System (ADS)

Noothout, Julia M. H.; de Vos, Bob D.; Wolterink, Jelmer M.; Išgum, Ivana

2018-03-01

Morphological analysis and identification of pathologies in the aorta are important for cardiovascular diagnosis and risk assessment in patients. Manual annotation is time-consuming and cumbersome in CT scans acquired without contrast enhancement and with low radiation dose. Hence, we propose an automatic method to segment the ascending aorta, the aortic arch and the thoracic descending aorta in low-dose chest CT without contrast enhancement. Segmentation was performed using a dilated convolutional neural network (CNN), with a receptive field of 131 × 131 voxels, that classified voxels in axial, coronal and sagittal image slices. To obtain a final segmentation, the obtained probabilities of the three planes were averaged per class, and voxels were subsequently assigned to the class with the highest class probability. Two-fold cross-validation experiments were performed where ten scans were used to train the network and another ten to evaluate the performance. Dice coefficients of 0.83 +/- 0.07, 0.86 +/- 0.06 and 0.88 +/- 0.05, and Average Symmetrical Surface Distances (ASSDs) of 2.44 +/- 1.28, 1.56 +/- 0.68 and 1.87 +/- 1.30 mm were obtained for the ascending aorta, the aortic arch and the descending aorta, respectively. The results indicate that the proposed method could be used in large-scale studies analyzing the anatomical location of pathology and morphology of the thoracic aorta.

[Effects of shortened mandibular dental arch on human brain activity during chewing: an fMRI study].

PubMed

Shoi, Kazuhito

2014-03-01

According to the shortened dental arch concept, missing molars should not always be restored with prosthetic treatment. A shortened dental arch with missing molars is associated with a decrease in masticatory function. However, it is not known whether a shortened dental arch influences brain activity during chewing. This study aimed to clarify the effect of posterior arch length of mandibular bilateral distal extension removable partial dentures (RPDs) on brain activity during chewing. Eleven subjects with bilaterally missing mandibular molars (mean age, 66.1 years) participated in the study. RPDs with full dental arch and shortened dental arch were fabricated and brain activity during gum chewing under each dental condition was measured using functional magnetic resonance imaging. Brain activation during gum chewing with the full dental arch was observed in the middle frontal gyrus, primary sensorimotor cortex extending to the premotor cortex, supplementary motor area, putamen, insula and cerebellum. However, activation of the middle frontal gyrus was not observed during gum chewing with the shortened dental arch. The results of this study suggest that human brain activity during chewing in the middle frontal gyrus may be associated with chewing in the presence of the molar region.

Human evaluation in association to the mathematical analysis of arch forms: Two-dimensional study.

PubMed

Zabidin, Nurwahidah; Mohamed, Alizae Marny; Zaharim, Azami; Marizan Nor, Murshida; Rosli, Tanti Irawati

2018-03-01

To evaluate the relationship between human evaluation of the dental-arch form, to complete a mathematical analysis via two different methods in quantifying the arch form, and to establish agreement with the fourth-order polynomial equation. This study included 64 sets of digitised maxilla and mandible dental casts obtained from a sample of dental arch with normal occlusion. For human evaluation, a convenient sample of orthodontic practitioners ranked the photo images of dental cast from the most tapered to the less tapered (square). In the mathematical analysis, dental arches were interpolated using the fourth-order polynomial equation with millimetric acetate paper and AutoCAD software. Finally, the relations between human evaluation and mathematical objective analyses were evaluated. Human evaluations were found to be generally in agreement, but only at the extremes of tapered and square arch forms; this indicated general human error and observer bias. The two methods used to plot the arch form were comparable. The use of fourth-order polynomial equation may be facilitative in obtaining a smooth curve, which can produce a template for individual arch that represents all potential tooth positions for the dental arch. Copyright © 2018 CEO. Published by Elsevier Masson SAS. All rights reserved.

35. ALTERNATE DESIGN USING THROUGH ARCH SPANS, WITH ARCH REPEATED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. ALTERNATE DESIGN USING THROUGH ARCH SPANS, WITH ARCH REPEATED BETWEEN TOWER LEGS, AND ASHLAR MASONRY WALLS AND PYLONS Pen-and-ink drawing by project architect Alfred Eichler, 1934. - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

Mesodermal retinoic acid signaling regulates endothelial cell coalescence in caudal pharyngeal arch artery vasculogenesis

PubMed Central

Li, Peng; Pashmforoush, Mohammad; Sucov, Henry M.

2011-01-01

Disruption of retinoic acid signaling causes a variety of pharyngeal arch artery and great vessel defects, as well as malformations in many other tissues, including those derived from the pharyngeal endoderm. Previous studies implied that arch artery defects in the context of defective RA signaling occur secondary to pharyngeal pouch segmentation defects, although this model has never been experimentally verified. In this study, we examined arch artery morphogenesis during mouse development, and the role of RA in this process. We show in normal embryos that the arch arteries form by vasculogenic differentiation of pharyngeal mesoderm. Using various genetic backgrounds and tissue-specific mutation approaches, we segregate pharyngeal arch artery and pharyngeal pouch defects in RA receptor mutants, and show that RA signal transduction only in pharyngeal mesoderm is required for arch artery formation. RA does not control pharyngeal mesodermal differentiation to endothelium, but instead promotes the aggregation of endothelial cells into nascent vessels. Expression of VE-cadherin was substantially reduced in RAR mutants, and this deficiency may underlie the arch artery defects. The consequences of disrupted mesodermal and endodermal RA signaling were restricted to the 4th and 6th arch arteries and to the 4th pharyngeal pouch, respectively, suggesting that different regulatory mechanisms control the formation of the more anterior arch arteries and pouches. PMID:22040871

A Comparative Evaluation of Accuracy of the Dies Affected by Tray Type, Material Viscosity, and Pouring Sequence of Dual and Single Arch Impressions- An In vitro Study

PubMed Central

Kulkarni, Rahul S.; Shah, Rupal J.; Chhajlani, Rahul; Saklecha, Bhuwan; Maru, Kavita

2017-01-01

Introduction The clinician’s skill, impression techniques, and materials play a very important role in recording fine details in an impression for accuracy of fixed partial denture prosthesis. Impression of prepared teeth and of the opposing arch can be recorded simultaneously by dual-arch trays, while the full arch metal trays are used for impressions of prepared teeth in one arch. Aim To measure and compare the accuracy of working dies made from impressions with metal and plastic dual arch trays and metal full arch trays, for two viscosities of impression material and by changing the sequence of pour of working and non-working sides. Materials and Methods A balanced design with independent samples was used to study the three variables (tray type, impression material viscosity, and pouring sequence). An impression made by dual arch trays and single arch trays were divided in to three groups (Group A-plastic dual arch tray, Group B-metal dual arch tray, Group C-full arch metal stock tray). Out of these three groups, two groups (Group A and B) were subdivided in to four subgroups each and one group (Group C) was subdivided in to two subgroups. A sample size of 30 was used in each subgroup yielding a total 300 impressions in three groups or ten subgroups. Impressions were made of a machined circular stainless steel die. All three dimensions (Occlusogingival, Mesiodistal, and Buccolingual) of the working dies as well as stainless steel standard die were measured three times, and the mean was used for the three standard sample values to which all working dies means were compared. Statistical analysis used for this study was a 3-factor analysis of variance with hypothesis testing at α =0.05. Results With respect to the selection of impression material viscosity statistically significant differences were found in the dies for the buccolingual and mesiodistal dimensions. Metal dual arch trays were slightly more accurate in the mesiodistal dimension in comparison to the plastic trays in reference of tray selection and in view of pouring sequence no differences were observed in occlusogingival dimension but in buccolingual and mesiodistal dimensions nonworking side was more accurate. Conclusion The gypsum dies produced from the dual arch impressions were generally smaller in all three dimensions than the stainless steel standard die. Plastic dual-arch trays were more accurate with rigid impression material and there was not statistically significant difference for sequence of pouring. Metal dual-arch trays were more accurate with monophase impression material and working side was more accurate. Stock metal full arch trays were more accurate for monophase impression material. PMID:28571280

Is arch form influenced by sagittal molar relationship or Bolton tooth-size discrepancy?

PubMed

Aldrees, Abdullah M; Al-Shujaa, Abdulmajeed M; Alqahtani, Mohammad A; Aljhani, Ali S

2015-06-26

Orthodontic patients show high prevalence of tooth-size discrepancy. This study investigates the possible association between arch form, clinically significant tooth-size discrepancy, and sagittal molar relationship. Pretreatment orthodontic casts of 230 Saudi patients were classified into one of three arch form types (tapered, ovoid, and square) using digitally scanned images of the mandibular arches. Bolton ratio was calculated, sagittal molar relationship was defined according to Angle classification, and correlations were analyzed using ANOVA, chi-square, and t-tests. No single arch form was significantly more common than the others. Furthermore, no association was observed between the presence of significant Bolton discrepancy and the sagittal molar relationship or arch form. Overall Bolton discrepancy is significantly more prevalent in males. Arch form in a Saudi patient group is independent of gender, sagittal molar relationship, and Bolton discrepancy.

Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study

PubMed Central

D’Souza, Ivor M; Kumar, H. C. Kiran; Shetty, K. Sadashiva

2015-01-01

Introduction: Transverse deficiency of the maxilla is a common clinical problem in orthodontics and dentofacial orthopedics. Transverse maxillary deficiency, isolated or associated with other dentofacial deformities, results in esthetic and functional impairment giving rise to several clinical manifestations such as asymmetrical facial growth, positional and functional mandibular deviations, altered dentofacial esthetics, adverse periodontal responses, unstable dental tipping, and other functional problems. Orthopedic maxillary expansion is the preferred treatment approach to increase the maxillary transverse dimension in young patients by splitting of the mid palatal suture. This orthopedic procedure has lately been subject of renewed interest in orthodontic treatment mechanics because of its potential for increasing arch perimeter to alleviate crowding in the maxillary arch without adversely affecting facial profile. Hence, the present investigation was conducted to establish a correlation between transverse expansion and changes in the arch perimeter, arch width and arch length. Methods: For this purpose, 10 subjects (five males, five females) were selected who had been treated by rapid maxillary expansion (RME) using hyrax rapid palatal expander followed by fixed mechanotherapy (PEA). Pretreatment (T1), postexpansion (T2), and posttreatment (T3) dental models were compared for dental changes brought about by RME treatment and its stability at the end of fixed mechanotherapy. After model measurements were made, the changes between T1–T2, T2–T3 and T1–T3 were determined for each patient. The mean difference between T1–T2, T2–T3 and T1–T3 were compared to assess the effects of RME on dental arch measurements. Results are expressed as mean ± standard deviation and are compared by repeated measures analysis of variance followed by a post-hoc test. Arch perimeter changes are correlated with changes in arch widths at the canine, premolar and molar regions. Results: The intercanine arch width increased by 2.9 mm, inter first premolar width increased by 3.2 mm, inter second premolar width increased by 4.6 mm, intermolar width increased by 4.4 mm, arch perimeter increased by 3.2 mm, arch length decreased by 1.8 mm from pretreatment to posttreatment. There is a strong positive correlation of arch perimeter with intercanine width (r2 = 0.99), interpremolar width (r2 = 0.99) and intermolar width (r2 = 0.98), indicating that there is a significant increase in arch perimeter with increase in arch width at the canine, premolars and molar regions. Conclusion: Findings of this study demonstrate that there was a significant increase in the intercanine, inter first premolar, inter second premolar intermolar arch width and arch perimeter from pretreatment to postexpansion, which was stable at the end of fixed mechanotherapy (PEA). There was a nonsignificant decrease in arch length from pretreatment to postexpansion that further decreased nonsignificantly from postexpansion to posttreatment. PMID:25684912

Dental arch dimensions, form and tooth size ratio among a Saudi sample

PubMed Central

Omar, Haidi; Alhajrasi, Manar; Felemban, Nayef; Hassan, Ali

2018-01-01

Objectives: To determine the dental arch dimensions and arch forms in a sample of Saudi orthodontic patients, to investigate the prevalence of Bolton anterior and overall tooth size discrepancies, and to compare the effect of gender on the measured parameters. Methods: This study is a biometric analysis of dental casts of 149 young adults recruited from different orthodontic centers in Jeddah, Saudi Arabia. The dental arch dimensions were measured. The measured parameters were arch length, arch width, Bolton’s ratio, and arch form. The data were analyzed using IBM SPSS software version 22.0 (IBM Corporation, New York, USA); this cross-sectional study was conducted between April 2015 and May 2016. Results: Dental arch measurements, including inter-canine and inter-molar distance, were found to be significantly greater in males than females (p<0.05). The most prevalent dental arch forms were narrow tapered (50.3%) and narrow ovoid (34.2%), respectively. The prevalence of tooth size discrepancy in all cases was 43.6% for anterior ratio and 24.8% for overall ratio. The mean Bolton’s anterior ratio in all malocclusion classes was 79.81%, whereas the mean Bolton’s overall ratio was 92.21%. There was no significant difference between males and females regarding Bolton’s ratio. Conclusion: The most prevalent arch form was narrow tapered, followed by narrow ovoid. Males generally had larger dental arch measurements than females, and the prevalence of tooth size discrepancy was more in Bolton’s anterior teeth ratio than in overall ratio. PMID:29332114

Preliminary Design of ArchE: A Software Architecture Design Assistant

DTIC Science & Technology

2003-09-01

This report presents a procedure for moving from a set of quality attribute scenarios to an architecture design that satisfies those scenarios. This...procedure is embodied in a preliminary design for an architecture design assistant named ArchE (Architecture Expert), which will be implemented on a

Image-Based Computational Fluid Dynamics in Blood Vessel Models: Toward Developing a Prognostic Tool to Assess Cardiovascular Function Changes in Prolonged Space Flights

NASA Technical Reports Server (NTRS)

Chatzimavroudis, George P.; Spirka, Thomas A.; Setser, Randolph M.; Myers, Jerry G.

2004-01-01

One of NASA's objectives is to be able to perform a complete, pre-flight, evaluation of cardiovascular changes in astronauts scheduled for prolonged space missions. Computational fluid dynamics (CFD) has shown promise as a method for estimating cardiovascular function during reduced gravity conditions. For this purpose, MRI can provide geometrical information, to reconstruct vessel geometries, and measure all spatial velocity components, providing location specific boundary conditions. The objective of this study was to investigate the reliability of MRI-based model reconstruction and measured boundary conditions for CFD simulations. An aortic arch model and a carotid bifurcation model were scanned in a 1.5T Siemens MRI scanner. Axial MRI acquisitions provided images for geometry reconstruction (slice thickness 3 and 5 mm; pixel size 1x1 and 0.5x0.5 square millimeters). Velocity acquisitions provided measured inlet boundary conditions and localized three-directional steady-flow velocity data (0.7-3.0 L/min). The vessel walls were isolated using NIH provided software (ImageJ) and lofted to form the geometric surface. Constructed and idealized geometries were imported into a commercial CFD code for meshing and simulation. Contour and vector plots of the velocity showed identical features between the MRI velocity data, the MRI-based CFD data, and the idealized-geometry CFD data, with less than 10% differences in the local velocity values. CFD results on models reconstructed from different MRI resolution settings showed insignificant differences (less than 5%). This study illustrated, quantitatively, that reliable CFD simulations can be performed with MRI reconstructed models and gives evidence that a future, subject-specific, computational evaluation of the cardiovascular system alteration during space travel is feasible.

Image-based computational fluid dynamics in blood vessel models: toward developing a prognostic tool to assess cardiovascular function changes in prolonged space flights

NASA Astrophysics Data System (ADS)

Chatzimavroudis, George P.; Spirka, Thomas A.; Setser, Randolph M.; Myers, Jerry G.

2005-04-01

One of NASA"s objectives is to be able to perform a complete pre-flight evaluation of possible cardiovascular changes in astronauts scheduled for prolonged space missions. Blood flow is an important component of cardiovascular function. Lately, attention has focused on using computational fluid dynamics (CFD) to analyze flow with realistic vessel geometries. MRI can provide detailed geometrical information and is the only clinical technique to measure all three spatial velocity components. The objective of this study was to investigate the reliability of MRI-based model reconstruction for CFD simulations. An aortic arch model and a carotid bifurcation model were scanned in a 1.5T MRI scanner. Axial MRI acquisitions provided images for geometry reconstruction using different resolution settings. The vessel walls were identified and the geometry was reconstructed using existing software. The geometry was then imported into a commercial CFD package for meshing and numerical solution. MRI velocity acquisitions provided true inlet boundary conditions for steady flow, as well as three-directional velocity data at several locations. In addition, an idealized version of each geometry was created from the model drawings. Contour and vector plots of the velocity showed identical features between the MRI velocity data, the MRI-based CFD data, and the idealized-geometry CFD data, with mean differences <10%. CFD results from different MRI resolution settings did not show significant differences (<5%). This study showed quantitatively that reliable CFD simulations can be performed in models reconstructed from MRI acquisitions and gives evidence that a future, subject-specific, computational evaluation of the cardiovascular system is possible.

Anchorage condition during canine retraction using transpalatal arch with continuous and segmented arch mechanics.

PubMed

Alhadlaq, Adel; Alkhadra, Thamer; El-Bialy, Tarek

2016-05-01

To compare anchorage condition in cases in which transpalatal arch was used to enhance anchorage in both continuous and segmented arch techniques. Twenty cases that required first premolar extraction for orthodontic treatment and transpalatal arch to enhance anchorage were included in this study. Ten cases were treated using the continuous arch technique, while the other 10 cases were treated using 0.019 × 0.025-inch TMA T-loops with posterior anchorage bend according to the Burstone and Marcotte description. Lateral cephalometric analysis of before and after canine retraction was performed using Ricketts analysis to measure the anteroposterior position of the upper first molar to the vertical line from the Pt point. Data were analyzed using an independent sample t-test. There was a statistically significant forward movement of the upper first molar in cases treated by continuous arch mechanics (4.5 ± 3.0 mm) compared with segmented arch mechanics (-0.7 ± 1.4 mm; P  =  .01). The posterior anchorage bend to T-loop used to retract the maxillary canine can enhance anchorage during maxillary canine retraction.

Relationship between lumbar changes and modifications in the plantar arch in women with low back pain

PubMed Central

Borges, Cláudia dos Santos; Fernandes, Luciane Fernanda Rodrigues Martinho; Bertoncello, Dernival

2013-01-01

OBJECTIVE : Evaluate the probable relationship among plantar arch, lumbar curvature, and low back pain. METHODS : Fifteen healthy women were assessed taking in account personal data and anthropometric measurements, photopodoscopic evaluation of the plantar arch, and biophotogrammetric postural analysis of the patient (both using the SAPO software), as well as evaluation of lumbar pain using a Visual Analog Scale (VAS). The average age of the participants was 30.45 (±6.25) years. RESULTS : Of the feet evaluated, there were six individuals with flat feet, five with high arch, and four with normal feet. All reported algic syndrome in the lumbar spine, with the highest VAS values for the volunteers with high arch. Correlation was observed between the plantar arch and the angle of the lumbar spine (r = -0.71, p = 0.004) Conclusion: High arch was correlated with more intense algic syndrome, while there was moderate positive correlation between flat foot and increased lumbar curvature, and between high arch and lumbar correction. Level of Evidence IV. Case Series. PMID:24453656

A Foot-Arch Parameter Measurement System Using a RGB-D Camera.

PubMed

Chun, Sungkuk; Kong, Sejin; Mun, Kyung-Ryoul; Kim, Jinwook

2017-08-04

The conventional method of measuring foot-arch parameters is highly dependent on the measurer's skill level, so accurate measurements are difficult to obtain. To solve this problem, we propose an autonomous geometric foot-arch analysis platform that is capable of capturing the sole of the foot and yields three foot-arch parameters: arch index (AI), arch width (AW) and arch height (AH). The proposed system captures 3D geometric and color data on the plantar surface of the foot in a static standing pose using a commercial RGB-D camera. It detects the region of the foot surface in contact with the footplate by applying the clustering and Markov random field (MRF)-based image segmentation methods. The system computes the foot-arch parameters by analyzing the 2/3D shape of the contact region. Validation experiments were carried out to assess the accuracy and repeatability of the system. The average errors for AI, AW, and AH estimation on 99 data collected from 11 subjects during 3 days were -0.17%, 0.95 mm, and 0.52 mm, respectively. Reliability and statistical analysis on the estimated foot-arch parameters, the robustness to the change of weights used in the MRF, the processing time were also performed to show the feasibility of the system.

Analysis of rotational and sliding collapse modes of masonry arches via Durand-Claye's method

NASA Astrophysics Data System (ADS)

Barsotti, Riccardo; Aita, Danila; Bennati, Stefano

2017-11-01

In this paper the mechanical behavior of circular and pointed masonry arches subject to their own weight is examined in order to determine their collapse modes. Different arch's shapes and thicknesses are considered; the influence of the friction coefficient on the arch collapse is analyzed as well. The safety level of arches is investigated by suitably reworking in semi-analytical form the stability area graphical method proposed by a renowned 19th century French scholar, Durand-Claye. Our analysis enables accounting for any given eccentricity of the thrust at the crown; furthermore, also the strength of masonry is taken into account. According to Durand-Claye's method, the arch is safe if along any given joint both the bending moment and the shear force do not exceed some given limit values. It is shown that attainment of a limit condition according to Durand-Claye corresponds to the onset of a collapse mechanism characterized by either relative rotation or sliding between masonry units. All possible symmetric collapse modes for an arch are thoroughly described. As it was expected, pointed and circular arches show different collapse behaviors. Limit values of arch thickness and friction coefficient are assessed. The results obtained are compared with those given by Michon in 1857.

Pregnancy Leads to Lasting Changes in Foot Structure

PubMed Central

Segal, Neil A.; Boyer, Elizabeth R.; Teran-Yengle, Patricia; Glass, Natalie; Hillstrom, Howard J.; Yack, H. John

2013-01-01

Objective Women are disproportionately affected by musculoskeletal disorders. Parous women appear to be at particularly elevated risk for structural and functional changes in the lower limbs. The combination of increased weight on joints with potentially greater laxity during pregnancy could lead to permanent structural changes in feet. Although arches may become lax during pregnancy, it is unknown whether changes persist. The objective of this study was to determine whether arch height loss persists postpartum. Design Forty-nine women completed this longitudinal study. Static and dynamic arch measurements were collected in first-trimester and at 19 weeks postpartum. Linear mixed models were used to determine whether outcome measures significantly changed overall or by parity. Results Arch height and rigidity index significantly decreased, with concomitant increases in foot length and arch drop. The first pregnancy accounted for the reduction in arch rigidity and increases in foot length and arch drop. No changes were detected in the center of pressure excursion index. Conclusions Pregnancy appears to be associated with a permanent loss of arch height and the first pregnancy may be the most significant. These changes in the feet could contribute to the increased risk for musculoskeletal disorders in women. Further research should assess the efficacy of rehabilitative interventions for prevention of pregnancy-related arch drop. PMID:23117270

A Foot-Arch Parameter Measurement System Using a RGB-D Camera

PubMed Central

Kong, Sejin; Mun, Kyung-Ryoul; Kim, Jinwook

2017-01-01

The conventional method of measuring foot-arch parameters is highly dependent on the measurer’s skill level, so accurate measurements are difficult to obtain. To solve this problem, we propose an autonomous geometric foot-arch analysis platform that is capable of capturing the sole of the foot and yields three foot-arch parameters: arch index (AI), arch width (AW) and arch height (AH). The proposed system captures 3D geometric and color data on the plantar surface of the foot in a static standing pose using a commercial RGB-D camera. It detects the region of the foot surface in contact with the footplate by applying the clustering and Markov random field (MRF)-based image segmentation methods. The system computes the foot-arch parameters by analyzing the 2/3D shape of the contact region. Validation experiments were carried out to assess the accuracy and repeatability of the system. The average errors for AI, AW, and AH estimation on 99 data collected from 11 subjects during 3 days were −0.17%, 0.95 mm, and 0.52 mm, respectively. Reliability and statistical analysis on the estimated foot-arch parameters, the robustness to the change of weights used in the MRF, the processing time were also performed to show the feasibility of the system. PMID:28777349

Relationship between vertical facial patterns and dental arch form in class II malocclusion.

PubMed

Grippaudo, Cristina; Oliva, Bruno; Greco, Anna Lucia; Sferra, Simone; Deli, Roberto

2013-11-07

The purpose of this study is to evaluate the relationship between dental arch form and the vertical facial pattern determined by the angle between the mandibular plane and the anterior cranial base (Sella-nasion/mandibular plane angle (SN-MP)) in skeletal class II untreated patients. A sample of 73 Caucasians patients with untreated skeletal class II in permanent dentition was divided into three groups according to the values of the angle SN-MP. An evaluation of the arch form was performed by angular and linear relation values on each patient. Regression analysis was used to determine the statistical significance of the relationships between SN-MP angle and dental arch form. The differences among the three groups were analyzed for significance using a variance analysis. A decrease of the upper arch transversal diameters in high SN-MP angle patients and an increase in low angle SN-MP ones (P<0.05) were shown. Result analysis showed a change in upper arch shape, with a smaller intercanine width in patients with high SN-MP angle and a greater one in low angle patients. As SN-MP angle increased, the upper arch form tended to be narrower. No statistically significant difference in mandibular arch form among the three groups was found, except the angle value related to incisors position. The results showed the association between the upper dental arch form and the vertical facial pattern. On the contrary, the lower arch form was not related to the mandibular divergence.

Nonlinear Buckling Analysis of Functionally Graded Graphene Reinforced Composite Shallow Arches with Elastic Rotational Constraints under Uniform Radial Load.

PubMed

Huang, Yonghui; Yang, Zhicheng; Liu, Airong; Fu, Jiyang

2018-05-28

The buckling behavior of functionally graded graphene platelet-reinforced composite (FG-GPLRC) shallow arches with elastic rotational constraints under uniform radial load is investigated in this paper. The nonlinear equilibrium equation of the FG-GPLRC shallow arch with elastic rotational constraints under uniform radial load is established using the Halpin-Tsai micromechanics model and the principle of virtual work, from which the critical buckling load of FG-GPLRC shallow arches with elastic rotational constraints can be obtained. This paper gives special attention to the effect of the GPL distribution pattern, weight fraction, geometric parameters, and the constraint stiffness on the buckling load. The numerical results show that all of the FG-GPLRC shallow arches with elastic rotational constraints have a higher buckling load-carrying capacity compared to the pure epoxy arch, and arches of the distribution pattern X have the highest buckling load among four distribution patterns. When the GPL weight fraction is constant, the thinner and larger GPL can provide the better reinforcing effect to the FG-GPLRC shallow arch. However, when the value of the aspect ratio is greater than 4, the flakiness ratio is greater than 103, and the effect of GPL's dimensions on the buckling load of the FG-GPLRC shallow arch is less significant. In addition, the buckling model of FG-GPLRC shallow arch with elastic rotational constraints is changed as the GPL distribution patterns or the constraint stiffness changes. It is expected that the method and the results that are presented in this paper will be useful as a reference for the stability design of this type of arch in the future.

The association of foot arch posture and prior history of shoulder or elbow surgery in elite-level baseball pitchers.

PubMed

Feigenbaum, Luis A; Roach, Kathryn E; Kaplan, Lee D; Lesniak, Bryson; Cunningham, Sean

2013-11-01

Case-control. The specific aim of this study was to examine the association between abnormal foot arch postures and a history of shoulder or elbow surgery in baseball pitchers. Pitching a baseball generates forces throughout the musculoskeletal structures of the upper and lower limbs. Structures such as the longitudinal arch of the foot are adaptable to stresses over time. Repeated pitching-related stresses may contribute to acquiring abnormal foot arch postures. Inversely, congenitally abnormal foot arch posture may lead to altered stresses of the upper limb during pitching. A convenience sample of 77 pitchers was recruited from a Division I university team and a professional baseball franchise. Subjects who had a history of shoulder or elbow surgery to the pitching arm were classified as cases. Subjects who met the criteria for classification of pes planus or pes cavus based on longitudinal arch angle were classified as having abnormal foot arch posture. Odds ratios were calculated to examine the association between abnormal foot arch posture and pitching-arm injury requiring surgery. Twenty-three subjects were classified as cases. The odds of being a case were 3.4 (95% confidence interval: 1.2, 9.6; P = .02) times greater for subjects with abnormal foot arch posture and 2.9 (95% confidence interval: 1.0, 8.1; P = .04) times greater for subjects with abnormal foot posture on the lunge leg. Abnormal foot arch posture and a surgical history in the pitching shoulder or elbow may be associated. Because the foot and its arches are adaptable and change over time, the pathomechanics of this association should be further explored.

Abnormal aortic arch morphology in Turner syndrome patients is a risk factor for hypertension.

PubMed

De Groote, Katya; Devos, Daniël; Van Herck, Koen; Demulier, Laurent; Buysse, Wesley; De Schepper, Jean; De Wolf, Daniël

2015-09-01

Hypertension in Turner syndrome (TS) is a multifactorial, highly prevalent and significant problem that warrants timely diagnosis and rigorous treatment. The objective of this study was to investigate the association between abnormal aortic arch morphology and hypertension in adult TS patients. This was a single centre retrospective study in 74 adult TS patients (age 29.41 ± 8.91 years) who underwent a routine cardiac MRI. Patients were assigned to the hypertensive group (N = 31) if blood pressure exceeded 140/90 mmHg and/or if they were treated with antihypertensive medication. Aortic arch morphology was evaluated on MRI images and initially assigned as normal (N = 54) or abnormal (N = 20), based on the curve of the transverse arch and the distance between the left common carotid-left subclavian artery. We additionally used a new more objective method to describe aortic arch abnormality in TS by determination of the relative position of the highest point of the transverse arch (AoHP). Logistic regression analysis showed that hypertension is significantly and independently associated with age, BMI and abnormal arch morphology, with a larger effect size for the new AoHP method than for the classical method. TS patients with hypertension and abnormal arch morphology more often had dilatation of the ascending aorta. There is a significant association between abnormal arch morphology and hypertension in TS patients, independent of age and BMI, and not related to other structural heart disease. We suggest that aortic arch morphology should be included in the risk stratification for hypertension in TS and propose a new quantitative method to express aortic arch morphology.

Zebrafish hox paralogue group 2 genes function redundantly as selector genes to pattern the second pharyngeal arch.

PubMed

Hunter, Michael P; Prince, Victoria E

2002-07-15

The pharyngeal arches are one of the defining features of the vertebrates, with the first arch forming the mandibles of the jaw and the second forming jaw support structures. The cartilaginous elements of each arch are formed from separate migratory neural crest cell streams, which derive from the dorsal aspect of the neural tube. The second and more posterior crest streams are characterized by specific Hox gene expression. The zebrafish has a larger overall number of Hox genes than the tetrapod vertebrates, as the result of a duplication event in its lineage. However, in both zebrafish and mouse, there are just two members of Hox paralogue group 2 (PG2): Hoxa2 and Hoxb2. Here, we show that morpholino-mediated "knock-down" of both zebrafish Hox PG2 genes results in major defects in second pharyngeal arch cartilages, involving replacement of ventral elements with a mirror-image duplication of first arch structures, and accompanying changes to pharyngeal musculature. In the mouse, null mutants of Hoxa2 have revealed that this single Hox gene is required for normal second arch patterning. By contrast, loss-of-function of either zebrafish Hox PG2 gene individually has no phenotypic consequence, showing that these two genes function redundantly to confer proper pattern to the second pharyngeal arch. We have also used hoxb1a mis-expression to induce localized ectopic expression of zebrafish Hox PG2 genes in the first arch; using this strategy, we find that ectopic expression of either Hox PG2 gene can confer second arch identity onto first arch structures, suggesting that the zebrafish Hox PG2 genes act as "selector genes." 2002 Elsevier Science (USA).

Comparison between rapid and mixed maxillary expansion through an assessment of arch changes on dental casts.

PubMed

Grassia, Vincenzo; d'Apuzzo, Fabrizia; Jamilian, Abdolreza; Femiano, Felice; Favero, Lorenzo; Perillo, Letizia

2015-01-01

Aim of this retrospective observational study was to compare upper and lower dental changes in patients treated with Rapid Maxillary Expansion (RME) and Mixed Maxillary Expansion (MME), assessed by dental cast analysis. Treatment groups consisted of 42 patients: the RME group (n = 21) consisted of 13 female and 8 male subjects with the mean age of 8.8 years ± 1.37 at T0 and 9.6 years ± 1.45 at T1; the MME group (n = 21) consisted of 12 female and 9 male patients with a mean age of 8.9 years ± 2.34 at T0 and 10.5 years ± 2.08 at T1. The upper and lower arch analysis was performed on four dental bilateral landmarks, on upper and lower casts; also upper and lower arch depths were measured. The groups were compared using independent sample t-test to estimate dental changes in upper and lower arches. Before expansion treatment (T0), the groups were similar for all examined variables (p>0.05). In both RME and MME group, significant increments in all the variables for maxillary and mandibular arch widths were observed after treatment. No significant differences in maxillary and mandibular arch depths were observed at the end of treatment in both groups. An evaluation of the changes after RME and MME (T1) showed statistically significant differences in mandibular arch depth (p<0.001) and maxillary intercanine widths (p<0.05). Differences in maxillary arch depth and arch width measurements were not significant. RME and MME can be considered two effective treatment options to improve transverse arch dimensions and gain space in the dental arches. A greater lower arch expansion was observed in the MME group, which might be attributed to the "lip bumper effects" observed in the MME protocol.

Aortic arch repair under moderate hypothermic circulatory arrest with or without antegrade cerebral perfusion based on the extent of repair

PubMed Central

Park, Sung Jun; Jeon, Bo Bae; Kim, Hee Jung

2018-01-01

Background For aortic-arch repair, moderate hypothermic circulatory arrest (HCA) have shown favorable outcomes over conventional deep HCA when coupled with antegrade cerebral perfusion (ACP); however, recent studies have shown that ACP may not be essential when circulatory arrest time is less than 30 minutes. This study aims to evaluate the stratified arch repair strategy of moderate HCA with or without ACP based on the extent of procedure. Methods Consecutive 138 patients (63 female; mean age, 60.2±15.7 years) undergoing open arch repair due to acute aortic syndrome (n=69) or chronic aneurysm (n=69) from January 2012 through April 2017 were enrolled in this study. Stratified neuroprotective strategy was employed according to the extent of repair: hemi-arch repair (n=93) was performed under moderated HCA alone and total-arch repair (n=45) under moderate HCA combined with unilateral ACP. Results Median total circulatory arrest and total procedural times were 8.0 minutes [interquartile range (IQR), 6.0–10.0] and 233.0 minutes (IQR, 196.0–290.0 minutes), respectively in the hemi-arch group, and 25.0 minutes (IQR, 12.0–33.0 minutes) and 349.0 minutes (IQR, 276.0–406.0 minutes), respectively in the total-arch group. Early mortality occurred in 2 patients (1.4%) who underwent hemi-arch repair for acute aortic dissection. There was no permanent neurological injury, but 2 cases (1.4%) of temporary neurologic deficit in the hemi-arch group. Other complications included re-exploration for bleeding in 6 (4.3%), postoperative extracorporeal life support in 5 (3.6%) and new-dialysis in 6 (4.3%). Conclusions Stratified cerebral perfusion strategy using moderate hypothermia for aortic-arch surgery based on the extent of arch repair showed satisfactory safety and reasonable efficiency. PMID:29707342

The Neural Crest in Cardiac Congenital Anomalies

PubMed Central

Keyte, Anna; Hutson, Mary Redmond

2012-01-01

This review discusses the function of neural crest as they relate to cardiovascular defects. The cardiac neural crest cells are a subpopulation of cranial neural crest discovered nearly 30 years ago by ablation of premigratory neural crest. The cardiac neural crest cells are necessary for normal cardiovascular development. We begin with a description of the crest cells in normal development, including their function in remodeling the pharyngeal arch arteries, outflow tract septation, valvulogenesis, and development of the cardiac conduction system. The cells are also responsible for modulating signaling in the caudal pharynx, including the second heart field. Many of the molecular pathways that are known to influence specification, migration, patterning and final targeting of the cardiac neural crest cells are reviewed. The cardiac neural crest cells play a critical role in the pathogenesis of various human cardiocraniofacial syndromes such as DiGeorge, Velocardiofacial, CHARGE, Fetal Alcohol, Alagille, LEOPARD, and Noonan syndromes, as well as Retinoic Acid Embryopathy. The loss of neural crest cells or their dysfunction may not always directly cause abnormal cardiovascular development, but are involved secondarily because crest cells represent a major component in the complex tissue interactions in the head, pharynx and outflow tract. Thus many of the human syndromes linking defects in the heart, face and brain can be better understood when considered within the context of a single cardiocraniofacial developmental module with the neural crest being a key cell type that interconnects the regions. PMID:22595346

[Sedation and anesthesia in dogs and cats with cardiovascular disease. II. Anesthesia planning with respect to pathophysiology, heart arrhythmia].

PubMed

Skarda, R T; Muir, W W; Bednarski, R M; Hubbell, J A; Mason, D E

1995-01-01

The purpose of this study was to review the incidence of cardiac arrhythmias in 137 anesthetized dogs and 13 anesthetized cats with congenital or acquired heart disease that were referred for correction of following procedures: patent ductus arteriosus (PDA-ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral thoracotomy (8.7%), correction of right aortic arch (ring anomaly, 3.3%), correction of subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with mitral regurgitation and congestive heart failure (2%), pericardectomy and removal of heart base tumor (2%), and palliative surgery for ventricular septal defect (VSD, 0.7%). The anesthetic plan considered the risks of anesthesia based upon the pathophysiology of cardiac lesions and the anesthetic drug effects on the cardiovascular system. Recommendations are made for dogs with decreased cardiac contractility, cardiac disease with volume overload, cardiac disease with pressure overload, and pericardial tamponade. The percentages of animals and their associated cardiac arrhythmias after premedication and during and after anesthesia were: sinus bradycardia (15.3%), sinus tachycardia (3.3%), atrial flutter (0.7%), atrial fibrillation (0.7%), premature ventricular contraction (14%), and ventricular tachycardia (1.3%). Prompt therapy was given to a percentage of animals in order to control arrhythmia and support cardiovascular system, by using atropine or glycopyrrolate (14%), lidocaine (17.3%), and dopamine (14.7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Ball motion and sliding friction in an arched outer-race ball bearing

NASA Technical Reports Server (NTRS)

Hamrock, B. J.

1974-01-01

The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is analyzed. Fatigue life evaluations were made. The analysis is applied to a 150-millimeter-bore ball bearing. The results indicated that for high-speed light-load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be optimal. Also, for an arched bearing a considerable amount of spinning occurs at the outer-race contacts.

Improving cardiovascular disease management in Australia: NPS MedicineWise.

PubMed

Gadzhanova, Svetla V; Roughead, Elizabeth E; Bartlett, Mark J

2013-08-05

To determine the impact of four NPS MedicineWise programs targeting quality use of medicines in cardiovascular management in primary care. Interrupted time-series analysis using the Department of Veterans' Affairs (DVA) claims dataset from 1 January 2002 to 31 August 2010. We examined the use of antithrombotics in people with atrial fibrillation and in those who had had a stroke, and the use of echocardiography and spironolactone in the population with heart failure. All veterans and their dependants in Australia who had received cardiovascular medicines or health services related to the targeted intervention. NPS MedicineWise national programs to improve cardiovascular management in primary care, which included prescriber feedback, academic detailing, case studies and audits as well as printed educational materials. Changes in medication and health service use before and after the interventions. All national programs were positively associated with significant improvements in related prescribing or test request practice. The interventions to improve the use of antithrombotics resulted in a 1.27% (95% CI, 1.26%-1.28%) and 0.63% (95% CI, 0.62%-0.64%) relative increase in the use of aspirin or warfarin in the population with atrial fibrillation 6 and 12 months after the program, respectively, and in a 1.51% (95% CI, 1.49%-1.53%) relative increase in the use of aspirin as monotherapy for secondary stroke prevention 12 months after the intervention. The heart failure programs resulted in a 3.69% (95% CI, 3.67%-3.71%) relative increase in the use of low-dose spironolactone and a 4.31% (95% CI, 4.27%-4.35%) relative increase in the use of echocardiogram tests 12 months after the intervention. NPS MedicineWise programs were effective in achieving positive changes in medicine and health service use for patients with cardiovascular diseases.

The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running

PubMed Central

McDonald, Kirsty A.; Stearne, Sarah M.; Alderson, Jacqueline A.; North, Ian; Pires, Neville J.; Rubenson, Jonas

2016-01-01

Elastic energy returned from passive-elastic structures of the lower limb is fundamental in lowering the mechanical demand on muscles during running. The purpose of this study was to investigate the two length-modulating mechanisms of the plantar fascia, namely medial longitudinal arch compression and metatarsophalangeal joint (MPJ) excursion, and to determine how these mechanisms modulate strain, and thus elastic energy storage/return of the plantar fascia during running. Eighteen runners (9 forefoot and 9 rearfoot strike) performed three treadmill running trials; unrestricted shod, shod with restricted arch compression (via an orthotic-style insert), and barefoot. Three-dimensional motion capture and ground reaction force data were used to calculate lower limb kinematics and kinetics including MPJ angles, moments, powers and work. Estimates of plantar fascia strain due to arch compression and MPJ excursion were derived using a geometric model of the arch and a subject-specific musculoskeletal model of the plantar fascia, respectively. The plantar fascia exhibited a typical elastic stretch-shortening cycle with the majority of strain generated via arch compression. This strategy was similar in fore- and rear-foot strike runners. Restricting arch compression, and hence the elastic-spring function of the arch, was not compensated for by an increase in MPJ-derived strain. In the second half of stance the plantar fascia was found to transfer energy between the MPJ (energy absorption) and the arch (energy production during recoil). This previously unreported energy transfer mechanism reduces the strain required by the plantar fascia in generating useful positive mechanical work at the arch during running. PMID:27054319

The effect of demographic features on aortic arch anatomy and its role in the etiology of cerebrovascular disease.

PubMed

İnanç, Yılmaz; İnanç, Yusuf; Ay, Halil

2018-01-01

The aim of this study was to retrospectively evaluate the distribution of aortic arches, the relationship with demographic characteristics, and the results of carotid and vertebral artery stenting procedures in patients diagnosed with cerebrovascular disease through the intra-arterial digital subtraction angiography (DSA) technique. A retrospective examination was performed on 288 patients diagnosed with cerebrovascular disease, who underwent DSA in the Department of Neurology of Gaziantep University Medical Faculty and Kahramanmaraş¸ Sütçü Imam University Medical Faculty. The patients were examined in respect of demographic features and aortic arch anatomic structure characteristics. All demographic characteristics, DSA, carotid, and vertebral artery stent results were recorded. The patients comprised 60.1% males and 39.9% females with a mean age of 58.25 years. Type 2 aortic arch was found in 175 (60.7%) patients, Type 2 aortic arch in 99 (34.3%) patients, and Type 3 aortic arch in 14 (4.8%) patients. The right carotid artery stenosis rate was found to be higher in patients with Type 2 aortic arch ( P =0.013). When the patients were evaluated according to the presence of a bovine arch, there was no significant difference in terms of age, carotid, and vertebral artery lesions ( P >0.05). The aortic arch and its branching properties were not found to have a direct effect on increased risk of cerebrovascular disease or stenting rates. This study can be considered to raise awareness for new studies to demonstrate the effect of aortic arch anatomic differences on cerebrovascular diseases.

The effect of demographic features on aortic arch anatomy and its role in the etiology of cerebrovascular disease

PubMed Central

İnanç, Yılmaz; İnanç, Yusuf; Ay, Halil

2018-01-01

Purpose The aim of this study was to retrospectively evaluate the distribution of aortic arches, the relationship with demographic characteristics, and the results of carotid and vertebral artery stenting procedures in patients diagnosed with cerebrovascular disease through the intra-arterial digital subtraction angiography (DSA) technique. Methods A retrospective examination was performed on 288 patients diagnosed with cerebrovascular disease, who underwent DSA in the Department of Neurology of Gaziantep University Medical Faculty and Kahramanmaraş¸ Sütçü Imam University Medical Faculty. The patients were examined in respect of demographic features and aortic arch anatomic structure characteristics. All demographic characteristics, DSA, carotid, and vertebral artery stent results were recorded. Results The patients comprised 60.1% males and 39.9% females with a mean age of 58.25 years. Type 2 aortic arch was found in 175 (60.7%) patients, Type 2 aortic arch in 99 (34.3%) patients, and Type 3 aortic arch in 14 (4.8%) patients. The right carotid artery stenosis rate was found to be higher in patients with Type 2 aortic arch (P=0.013). When the patients were evaluated according to the presence of a bovine arch, there was no significant difference in terms of age, carotid, and vertebral artery lesions (P>0.05). Conclusion The aortic arch and its branching properties were not found to have a direct effect on increased risk of cerebrovascular disease or stenting rates. This study can be considered to raise awareness for new studies to demonstrate the effect of aortic arch anatomic differences on cerebrovascular diseases. PMID:29302189

Effect of impeded medial longitudinal arch drop on vertical ground reaction force and center of pressure during static loading.

PubMed

Chen, Shing-Jye; Gielo-Perczak, Krystyna

2011-01-01

Arch supports commonly used to alleviate foot pain can impede the normal drop of medial longitudinal arch (MLA) thereby altering its function. The purpose of the study was to examine the effect of using arch supports on vertical ground reaction force (GRF) and center of pressure (COP) during simulated midstance while the foot was statically loaded. Ten healthy young subjects were recruited. Two dimensional (2D) analysis of the MLA was captured for both barefoot (BF) and arch support conditions before and after loading via a custom made weight loading apparatus. The foot was loaded and positioned to simulate the midstance phase of walking. Two-dimensional reflective markers demarcated the MLA and captured with the loaded foot on a force platform. The impeded MLA drop was compared between the unloaded BF, loaded BF and loaded arch support conditions. The vertical GRF, the anterior-posterior and the medial-lateral COP displacements were also measured in response to the impeded MLA by the arch supports. The arch supports impeded the MLA drop (p<0.05) and shifted the COP toward the medial side (p<0.05), specifically for the rearfoot (calcaneal segment region), but no changes were determined for the vertical GRF (p>0.05). The impedance of MLA drop by the arch support altered the pattern of the ML COP shift in the rearfoot region. The use of arch supports may not relieve painful foot conditions that are associated with excessive calcaneal eversion indicated by altering COP shifts in localized foot regions.

The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running.

PubMed

McDonald, Kirsty A; Stearne, Sarah M; Alderson, Jacqueline A; North, Ian; Pires, Neville J; Rubenson, Jonas

2016-01-01

Elastic energy returned from passive-elastic structures of the lower limb is fundamental in lowering the mechanical demand on muscles during running. The purpose of this study was to investigate the two length-modulating mechanisms of the plantar fascia, namely medial longitudinal arch compression and metatarsophalangeal joint (MPJ) excursion, and to determine how these mechanisms modulate strain, and thus elastic energy storage/return of the plantar fascia during running. Eighteen runners (9 forefoot and 9 rearfoot strike) performed three treadmill running trials; unrestricted shod, shod with restricted arch compression (via an orthotic-style insert), and barefoot. Three-dimensional motion capture and ground reaction force data were used to calculate lower limb kinematics and kinetics including MPJ angles, moments, powers and work. Estimates of plantar fascia strain due to arch compression and MPJ excursion were derived using a geometric model of the arch and a subject-specific musculoskeletal model of the plantar fascia, respectively. The plantar fascia exhibited a typical elastic stretch-shortening cycle with the majority of strain generated via arch compression. This strategy was similar in fore- and rear-foot strike runners. Restricting arch compression, and hence the elastic-spring function of the arch, was not compensated for by an increase in MPJ-derived strain. In the second half of stance the plantar fascia was found to transfer energy between the MPJ (energy absorption) and the arch (energy production during recoil). This previously unreported energy transfer mechanism reduces the strain required by the plantar fascia in generating useful positive mechanical work at the arch during running.

Origin and structural development of the LaSalle Arch, Louisiana

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawless, P.N.

1990-05-01

The LaSalle arch is a basement high separating the Louisiana and Mississippi interior salt basins. Using reflection seismic data, an area located on the southern end of the LaSalle arch was shown to be composed of relict Paleozoic continental crust that was left behind and partially rifted during the breakup of Pangea during the Triassic. Rifting preferentially occurred to the north of a Paleozoic thrust fault nose, and crustal extension took place in a northeast-southwest direction. The LaSalle arch, as seen in post-Triassic stratigraphy, formed by a two-part process. The western limb developed syndepositionally due to differential subsidence, and themore » eastern limb developed due to relative regional tilting to the east after deposition of the Claibornian Sparta Formation. The LaSalle arch acted as only a minor impediment to sediment transport with a very low relief except during the Tayloran Stage of the Upper Cretaceous. A single truncational unconformity in post-Triassic stratigraphy is present in the Taylora Demopolis Formation, indicating a period of relatively major uplift by the LaSalle arch. This contrast, with the Sabine arch in eastern Texas; the Sabine arch experienced uplift during the Eagle Fordian and Sabinian stages. A recently proposed hypothesis calling for overthrusting in the Western Cordillera as the mechanism for uplift on the Sabine arch cannot explain movement of the LaSalle arch because horizontal stress would predict synchronous uplift of basement highs. A more satisfactory uplift mechanism calls upon lateral heat flow from the mantle as the driving force for uplift.« less

Body weight and the medial longitudinal foot arch: high-arched foot, a hidden problem?

PubMed

Woźniacka, R; Bac, A; Matusik, S; Szczygieł, E; Ciszek, E

2013-05-01

This study had two objectives. First, to determine the prevalence of hollow (high-arched) and flat foot among primary school children in Cracow (Poland). Second, to evaluate the relationship between the type of medial longitudinal arch (MLA; determined by the Clarke's angle) and degree of fatness. The prevalence of underweight, overweight, and obesity was determined by means of IOTF cut-offs with respect to age and gender. A sample of 1,115 children (564 boys and 551 girls) aged between 3 and 13 years was analyzed. In all age groups, regardless of gender, high-arched foot was diagnosed in the majority of children. A distinct increase in the number of children with high-arched foot was observed between 7- and 8-year olds. Regardless of the gender, high-arched foot was more common among underweight children. In the group of obese children, the biggest differences were attributed to gender. High-arched foot was the most frequently observed among boys. In all gender and obesity level groups, the flat foot was more common among boys than among girls. High-arched foot is the most common foot defect among children 3-13 years old regardless of gender. Flat foot is least frequently observed in children 3-13 years old. A statistic correlation between MLA and adiposity is observed. Stronger correlation is observed among girls.

Effect of using truncated versus total foot length to calculate the arch height ratio.

PubMed

McPoil, Thomas G; Cornwall, Mark W; Vicenzino, Bill; Teyhen, Deydre S; Molloy, Joseph M; Christie, Douglas S; Collins, Natalie

2008-12-01

The purpose of this study was to determine the arch height ratio in a large cohort of subjects as well as to assess the reliability and validity of the foot measurements utilized in the study. Eight hundred and fifty subjects, 393 women and 457 men, consented to participate in the study. The dorsal arch height, total foot length, and the truncated foot length were used to calculate two variations of the arch height ratio. In addition to determining within- and between-rater measurement reliability, radiographs were used to establish validity. The truncated arch height ratio can be estimated using the total foot length, unless toe deformities are present in the individual being assessed. All foot measurements had high levels of intra- and inter-rater reliability and the validity of measuring the dorsal arch height while standing with equal weight on both feet was established. This investigation provides normative values from a large cohort of healthy female and male subjects for two variations of the arch height ratio. The arch height ratio is a reliable and valid measurement that may prove useful to clinicians and researchers for the classification of foot posture.

Influence of shovel-shaped incisors on the dental arch crowding in Mongolian females.

PubMed

Hasegawa, Yuh; Terada, Kazuto; Kageyama, Ikuo; Tsukada, Shin-ichi; Uzuka, Satoshi; Nakahara, Rizako; Nakahara, Sen

2009-08-01

The aim of this study was to investigate the influences of shovel-shaped incisors on the dental arch crowding in the samples of modern young female adult Mongolians (belonging to the Khalkha-Mogol grouping) ranged between 18.5 and 25.0 years, with a mean age of 20.7 years. Materials in this study comprised of 33 dental casts. Plaster replicas of the A.S.U. system plaques were used to facilitate standardization in scoring and classify shoveling regarding both upper central and lateral incisors. Dimensions of the dental arch namely, overjet, overbite, arch depth, arch width and irregularity index were measured. The correlation between the shovel shape of the central incisor and the lateral incisor was highly significant. Significantly relations were found between the grades of shoveling and the mesiodistal diameters of upper first molars and lower incisors. Positive correlation was admitted between the shoveling and upper arch depth anterior, and upper arch depth. It may be considered that the grades of shoveling are indirectly related with upper and/or lower anterior crowding. Although crowding is looks like an expression of disharmony between teeth and alveolar arch, it may be caused by multiple etiologic factors interacted directly and/or indirectly.

Novel Arch Bar Fabricated With a Computer-Aided Design and Three-Dimensional Printing: A Feasibility Study.

PubMed

He, Wei; Sun, Yuchun; Tian, Kaiyue; Xie, Xiaoyan; Wang, Xiaoxia; Li, Zili

2015-11-01

The aim of the present study was to evaluate the feasibility of the design and fabrication of a novel arch bar using 3-dimensional printing. Furthermore, the study assessed its use in a preliminary clinical study of intermaxillary fixation. Seven patients who met the inclusion criteria were enrolled in the present study. Plaster dental casts were created of each patient and scanned using cone-beam computed tomography to obtain digital casts. Computer-aided design software was then used to complete the virtual building of the arch bars, which were manufactured using 3-dimensional printing and a cobalt-chrome alloy. The clinical results were observed after the arch bars were fixed to the dentition with steel wires. The arch bar contacted the dentition with a "surface-to-surface" pattern. The utility of these novel arch bars was verified by successfully fitting them to the dental arches of the patients. All the patients achieved their desired occlusion. The results of the present study have illustrated that this digital method is feasible for constructing a novel arch bar, showing promise for clinical use. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Three-dimensional dental arch changes of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusion

PubMed Central

Peixoto, Adriano Porto; Pinto, Ary dos Santos; Garib, Daniela Gamba; Gonçalves, João Roberto

2014-01-01

Introduction This study assessed the three-dimensional changes in the dental arch of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusions at three different periods. Methods Landmarks previously identified on upper and lower dental casts were digitized on a three-dimensional digitizer MicroScribe-3DX and stored in Excel worksheets in order to assess the width, length and depth of patient's dental arches. Results During orthodontic preparation, the maxillary and mandibular transverse dimensions measured at the premolar regions were increased and maintained throughout the follow-up period. Intercanine width was increased only in the upper arch during orthodontic preparation. Maxillary arch length was reduced during orthodontic finalization, only. Upper and lower arch depths were stable in the study periods. Differences between centroid and gingival changes suggested that upper and lower arch premolars buccaly proclined during the pre-surgical period. Conclusions Maxillary and mandibular dental arches presented transverse expansion at premolar regions during preoperative orthodontic preparation, with a tendency towards buccal tipping. The transverse dimensions were not altered after surgery. No sagittal or vertical changes were observed during the follow-up periods. PMID:25279524

Modified protrusion arch for anterior crossbite correction - a case report.

PubMed

Roy, Abhishek Singha; Singh, Gulshan Kr; Tandon, Pradeep; Chaudhary, Ramsukh

2013-01-01

Borderline and mild skeletal Class III relationships in adult patients are usually treated by orthodontic camouflage. Reasonably rood results have been achieved with nonsurgical teatment of anterior crossbite. Class III malocclusion may be associated with mandibular prognathism, maxillary retrognathism, or both. Class III maxillary retrognathism generally involves anterior crossbite, which must be opened if upper labial brackets are to be bonded. If multiple teeth are in crossbite, after opening the bite usual step is to ligate forward or advancement arch made of 0.018" or 0.020" stainless steel or NiTi wire main arch that must be kept separated 2 mm from the slot ofupper incisor braces. Two stops or omegas are made 1 mm mesial to the tubes of the molar bands that will impede main arch from slipping,and in this manner the arch will push the anterior teeth forward Here we have fabricated a modified multiple loop protrusion arch to correct an anterior crossbite with severe crowding that was not amenable to correct by advancement arches.

Optimization of shallow arches against instability using sensitivity derivatives

NASA Technical Reports Server (NTRS)

Kamat, Manohar P.

1987-01-01

The author discusses the problem of optimization of shallow frame structures which involve a coupling of axial and bending responses. A shallow arch of a given shape and of given weight is optimized such that its limit point load is maximized. The cross-sectional area, A(x) and the moment of inertia, I(x) of the arch obey the relationship I(x) = rho A(x) sup n, n = 1,2,3 and rho is a specified constant. Analysis of the arch for its limit point calculation involves a geometric nonlinear analysis which is performed using a corotational formulation. The optimization is carried out using a second-order projected Lagrangian algorithm and the sensitivity derivatives of the critical load parameter with respect to the areas of the finite elements of the arch are calculated using implicit differentation. Results are presented for an arch of a specified rise to span ratio under two different loadings and the limitations of the approach for the intermediate rise arches are addressed.

Shortened dental arch and cerebral regional blood volume: an experimental pilot study with optical topography.

PubMed

Miyamoto, Ikuya; Yoshida, Kazuya; Bessho, Kazuhisa

2009-04-01

A shortened dental arch without posterior occlusal support has been thought to maintain sufficient oral function. The mechanism of occlusal adaptation with a shortened dental arch is unclear. For a better understanding of the effects of molar teeth on brain function, the authors combined experimentally-shortened dental arches and a neuro-imaging technique. Regional cerebral blood volume was measured using near-infrared optical topography during maximum voluntary clenching tasks from 10 subjects on individually fabricated oral appliances, which can create experimentally complete and shortened dental arches. Results suggested that clenching on the complete dental arch showed a significantly higher brain blood volume than that on the shortened dental arch. Moreover, there were no differences between the two splints in the latency to the maximum oxyhemoglobin concentration. These findings suggest that occlusal status is closely related to brain blood flow and lack of occlusal molar support rapidly reduces cerebral blood volume in the maximum voluntary clenching condition.

Developmental evidence for serial homology of the vertebrate jaw and gill arch skeleton

PubMed Central

Gillis, J. Andrew; Modrell, Melinda S.; Baker, Clare V. H.

2013-01-01

Gegenbaur’s classical hypothesis of jaw-gill arch serial homology is widely cited, but remains unsupported by either paleontological evidence (e.g. a series of fossils reflecting the stepwise transformation of a gill arch into a jaw) or developmental genetic data (e.g. shared molecular mechanisms underlying segment identity in the mandibular, hyoid and gill arch endoskeletons). Here we show that nested expression of Dlx genes – the “Dlx code” that specifies upper and lower jaw identity in mammals and teleosts – is a primitive feature of the mandibular, hyoid and gill arches of jawed vertebrates. Using fate-mapping techniques, we demonstrate that the principal dorsal and ventral endoskeletal segments of the jaw, hyoid and gill arches of the skate Leucoraja erinacea derive from molecularly equivalent mesenchymal domains of combinatorial Dlx gene expression. Our data suggest that vertebrate jaw, hyoid and gill arch cartilages are serially homologous, and were primitively patterned dorsoventrally by a common Dlx blueprint. PMID:23385581

Is there a prospect for hybrid aortic arch surgery?

PubMed

Bashir, Mohamad; Harky, Amer; Bilal, Haris

2018-05-16

The surge of endovascular repair of aortic aneurysm in current modern aortic surgery practice has been the key for surgical management of elective cases of thoracic aortic aneurysms. This has paved way for the combined hybrid approach to be amongst the armamentarium for the management of aortic arch disease. The pivotal understanding of the aortic arch natural history coupled with device technology advancement allowed surgeons insight into delivery of hybrid surgery with acceptable morbidity and mortality results. This review article provides current insights into hybrid technique of aortic arch aneurysm repair and the evidences behind its applicability to arch surgery. It is aimed to highlight the challenges encountered for this innovative approach and correlate its challenges to those that are met by the conventional open aortic arch repair.

Absent right common carotid artery associated with aberrant right subclavian artery.

PubMed

Uchino, Akira; Uwabe, Kazuhiko; Osawa, Iichiro

2018-06-01

Rarely, the external and internal carotid arteries arise separately from the brachiocephalic trunk and right subclavian artery (SA) or the aortic arch and reflect the absence of a common carotid artery (CCA). We report a 45-year-old man with absent right CCA associated with aberrant right SA, an extremely rare combination, diagnosed by computed tomography (CT) angiography during follow-up for postoperative aortic dissection. Retrospective careful observation of preoperative postcontrast CT revealed the absent right CCA. Previously reported arch variations associated with absent CCA include cervical aortic arch, double aortic arch, and right aortic arch.

Ball motion and sliding friction in an arched outer race ball bearing

NASA Technical Reports Server (NTRS)

Hamrock, B. J.

1973-01-01

The motion of the ball and sliding friction in an arched outer race ball bearing under thrust loads is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

Ball motion and sliding friction in an arched outer race ball bearing

NASA Technical Reports Server (NTRS)

Hamrock, B. J.

1974-01-01

The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

Angiotensin II modulates interleukin-1{beta}-induced inflammatory gene expression in vascular smooth muscle cells via interfering with ERK-NF-{kappa}B crosstalk

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Shanqin; Zhi, Hui; Hou, Xiuyun

2011-07-08

Highlights: {yields} We examine how angiotensin II modulates ERK-NF-{kappa}B crosstalk and gene expression. {yields} Angiotensin II suppresses IL-1{beta}-induced prolonged ERK and NF-{kappa}B activation. {yields} ERK-RSK1 signaling is required for IL-1{beta}-induced prolonged NF-{kappa}B activation. {yields} Angiotensin II modulates NF-{kappa}B responsive genes via regulating ERK-NF-{kappa}B crosstalk. {yields} ERK-NF-{kappa}B crosstalk is a novel mechanism regulating inflammatory gene expression. -- Abstract: Angiotensin II is implicated in cardiovascular diseases, which is associated with a role in increasing vascular inflammation. The present study investigated how angiotensin II modulates vascular inflammatory signaling and expression of inducible nitric oxide synthase (iNOS) and vascular cell adhesion molecule (VCAM)-1. Inmore » cultured rat aortic vascular smooth muscle cells (VSMCs), angiotensin II suppressed interleukin-1{beta}-induced prolonged phosphorylation of extracellular signal-regulated kinase (ERK) and ribosomal S6 kinase (RSK)-1, and nuclear translocation of nuclear factor (NF)-{kappa}B, leading to decreased iNOS but enhanced VCAM-1 expression, associated with an up-regulation of mitogen-activated protein kinase phosphatase-1 expression. Knock-down of RSK1 selectively down regulated interleukin-1{beta}-induced iNOS expression without influencing VCAM-1 expression. In vivo experiments showed that interleukin-1{beta}, iNOS, and VCAM-1 expression were detectable in the aortic arches of both wild-type and apolipoprotein E-deficient (ApoE{sup -/-}) mice. VCAM-1 and iNOS expression were higher in ApoE{sup -/-} than in wild type mouse aortic arches. Angiotensin II infusion (3.2 mg/kg/day, for 6 days, via subcutaneous osmotic pump) in ApoE{sup -/-} mice enhanced endothelial and adventitial VCAM-1 and iNOS expression, but reduced medial smooth muscle iNOS expression associated with reduced phosphorylation of ERK and RSK-1. These results indicate that angiotensin II can differentially modulate inflammatory gene expression in aortic smooth muscle cells through influencing ERK-NF-{kappa}B crosstalk, which may contribute to angiotensin II-induced inflammatory disorders related to cardiovascular diseases.« less

Reassessing the Dlx code: the genetic regulation of branchial arch skeletal pattern and development

PubMed Central

Depew, Michael J; Simpson, Carol A; Morasso, Maria; Rubenstein, John LR

2005-01-01

The branchial arches are meristic vertebrate structures, being metameric both between each other within the rostrocaudal series along the ventrocephalic surface of the embryonic head and within each individual arch: thus, just as each branchial arch must acquire a unique identity along the rostrocaudal axis, each structure within the proximodistal axis of an arch must also acquire a unique identity. It is believed that regional specification of metameric structures is controlled by the nested expression of related genes resulting in a regional code, a principal that is though to be demonstrated by the regulation of rostrocaudal axis development in animals exerted by the nested HOM-C/Hox homeobox genes. The nested expression pattern of the Dlx genes within the murine branchial arch ectomesenchyme has more recently led to the proposal of a Dlx code for the regional specification along the proximodistal axis of the branchial arches (i.e. it establishes intra-arch identity). This review re-examines this hypothesis, and presents new work on an allelic series of Dlx loss-of-function mouse mutants that includes various combinations of Dlx1, Dlx2, Dlx3, Dlx5 and Dlx6. Although we confirm fundamental aspects of the hypothesis, we further report a number of novel findings. First, contrary to initial reports, Dlx1, Dlx2 and Dlx1/2 heterozygotes exhibit alterations of branchial arch structures and Dlx2−/− and Dlx1/2−/− mutants have slight alterations of structures derived from the distal portions of their branchial arches. Second, we present evidence for a role for murine Dlx3 in the development of the branchial arches. Third, analysis of compound Dlx mutants reveals four grades of mandibular arch transformations and that the genetic interactions of cis first-order (e.g. Dlx5 and Dlx6), trans second-order (e.g. Dlx5 and Dlx2) and trans third-order paralogues (e.g. Dlx5 and Dlx1) result in significant and distinct morphological differences in mandibular arch development. We conclude by integrating functions of the Dlx genes within the context of a hypothesized general mechanism for the establishment of pattern and polarity in the first branchial arch of gnathostomes that includes regionally secreted growth factors such as Fgf8 and Bmp and other transcription factors such as Msx1, and is consistent both with the structure of the conserved gnathostome jaw bauplan and the elaboration of this bauplan to meet organismal end-point designs. PMID:16313391

Mathematical beta function formulation for maxillary arch form prediction in normal occlusion population.

PubMed

Mina, Morteza; Borzabadi-Farahani, Ali; Tehranchi, Azita; Nouri, Mahtab; Younessian, Farnaz

2017-04-01

The aim of this study was to assess the dental arch curvature in subjects with normal occlusion in an Iranian population and propose a beta function formula to predict maxillary arch form using the mandibular intermolar widths (IMW) and intermolar depths (IMD). The materials used were study casts of 54 adolescents with normal occlusion and mean age of 14.1 years (25 males, 29 females, age range 12-16 years). Curve-fitting analyses were carried out and the curves passing through the facial-axis point of the canines, premolars, first molars, and the incisal edges of the anterior teeth were studied using a 3D laser scanner. Using the measured IMW and IMD of the dental arches at the maxillary and mandibular first molar region, a beta function formula proposed for predicting maxillary arch form. The accuracy of the proposed formula was assessed on 10 randomly selected dental casts. The mean (SD) of the maxillary and mandibular IMW and IMD were 57.92 (4.75), 54.19 (5.31), and 31.59 (2.90) and 28.10 (2.59) mm, respectively. There was no gender dimorphism (P > 0.05) for both variables (IMW, IMD). There was a strong positive association (n = 10, Pearson r = 0.98, P < 0.05) between the measured (actual) maxillary arch length and proposed arch length derived from generated formula. The goodness of fit (whole arch) for the proposed beta function formula, using adjusted r square measure and root mean square in 10 patients averaged 0.97 and 1.49 mm, respectively. The corresponding figures for the maxillary anterior arch (canine to canine) were 0.90 and 0.92 mm, respectively. The proposed beta function formula used for predicting maxillary arch form based on two mandibular measures (IMW, IMD) was found to have a high accuracy for maxillary arch prediction in the Iranian population and may be used as a guide to fabricate customized arch wires or as an aid in maxillary reconstructive surgery.

10. Typical Masonry Longitudinal Section Arch Seven; Typical Masonry ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. Typical Masonry Longitudinal Section - Arch Seven; Typical Masonry Longitudinal Section - Arch Eight - Arlington Memorial Bridge, Spanning Potomac River between Lincoln Memorial & Arlington National Cemetery, Washington, District of Columbia, DC

Assessment of the influence of jogging on the shape of female foot arches.

PubMed

Maslon, Agata; Golec, Joanna; Szczygiel, Elzbieta; Czechowska, Dorota; Golec, Boguslaw

2017-12-23

Both walking and its faster, running, consist of cyclical subsequent phases of swing and support; however, they differ in their time proportions as well as magnitude of acting forces. There is a lack of studies concerning the long-term consequences of repeated jogging cycles on the function of feet and, above all, on their permanent impact on the shape of foot arches. The objective of this study was to answer the question whether regular jogging changes the shape of the transverse and medial longitudinal arches of the feet. The research material consisted of 96 women with an average age of 26.57, and included 50 actively jogging women, and 46 of non-joggers. The study was performed with the use of EMED-SF force platform. The plantar surface of the foot was divided into 10 regions according to Cavanagh, for which peak pressure and contact time were established. Two indicators were defined: metatarsal bone pressure distribution pattern acc. to Kantali, and longitudinal arch index acc. to Cavanagh. The data obtained revealed more frequent occurrence of the greatest pressure under the centrally located metatarsal heads (lack of functional foot transverse arch) among the female joggers, compared with the non-joggers. Moreover, the findings indicate the higher frequency of medial longitudinal foot arch flattening among female runners, with a great deal of consistency between both feet, whereas results for the control group show asymmetrical medial arch shapes with right foot propensity to normal arch shape and left foot tendency for excessive arch. The observed differences in feet arch shapes between female joggers and non-joggers indicate the influence of jogging on feet functional adaptations.

Interaction of arch type and footwear on running mechanics.

PubMed

Butler, Robert J; Davis, Irene S; Hamill, Joseph

2006-12-01

Running shoes are designed to accommodate various arch types to reduce the risk of lower extremity injuries sustained during running. Yet little is known about the biomechanical changes of running in the recommended footwear that may allow for a reduction in injuries. To evaluate the effects of motion control and cushion trainer shoes on running mechanics in low- and high-arched runners. Controlled laboratory study. Twenty high-arched and 20 low-arched recreational runners (>10 miles per week) were recruited for the study. Three-dimensional kinematic and kinetics were collected as subjects ran at 3.5 ms(-1) +/- 5% along a 25-m runway. The motion control shoe evaluated was the New Balance 1122, and the cushioning shoe evaluated was the New Balance 1022. Repeated-measures analyses of variance were used to determine if low- and high-arched runners responded differently to motion control and cushion trainer shoes. A significant interaction was observed in the instantaneous loading rate such that the low-arched runners had a lower instantaneous loading rate in the motion control condition, and the high-arched runners had a lower instantaneous loading rate in the cushion trainer condition. Significant main effects for shoe were observed for peak positive tibial acceleration, peak-to-peak tibial acceleration, mean loading rate, peak eversion, and eversion excursion. These results suggest that motion control shoes control rearfoot motion better than do cushion trainer shoes. In addition, cushion trainer shoes attenuate shock better than motion control shoes do. However, with the exception of instantaneous loading rate, these benefits do not differ between arch type. Running footwear recommendations should be based on an individual's running mechanics. If a mechanical analysis is not available, footwear recommendations can be based empirically on the individual's arch type.

Fenestrated endovascular repair of aortic arch aneurysm in patients with bovine arch using the Najuta stent graft.

PubMed

Toya, Naoki; Ohki, Takao; Fukushima, Soichiro; Shukuzawa, Kota; Ito, Eisaku; Akiba, Tadashi

2018-06-01

We describe the case of a 74-year-old man with a thoracic aortic aneurysm with a bovine arch who underwent fenestrated endovascular repair of aortic arch aneurysm using the Najuta stent graft (Kawasumi Laboratories, Inc, Tokyo, Japan). He has had a previous endovascular aneurysm repair and femoropopliteal bypass for abdominal aortic aneurysm combined with peripheral arterial disease. The Najuta stent graft was inserted and deployed at zone 0 with delicate positional adjustment of the fenestration of the stent graft to the brachiocephalic trunk. There was no endoleak or complication. His postoperative course was uneventful. At 7-month follow-up, complete exclusion of the aneurysm was noted. The Najuta stent graft repair of aortic arch aneurysms is a safe and effective treatment option for patients with a bovine arch.

Total Arch versus Hemiarch Replacement for Type A Acute Aortic Dissection: A Single-Center Experience.

PubMed

Lio, Antonio; Nicolò, Francesca; Bovio, Emanuele; Serrao, Andrea; Zeitani, Jacob; Scafuri, Antonio; Chiariello, Luigi; Ruvolo, Giovanni

2016-12-01

We retrospectively evaluated early and intermediate outcomes of aortic arch surgery in patients with type A acute aortic dissection (AAD), investigating the effect of arch surgery extension on postoperative results. From January 2006 through July 2013, 201 patients with type A AAD underwent urgent corrective surgery at our institution. Of the 92 patients chosen for this study, 59 underwent hemiarch replacement (hemiarch group), and 33 underwent total arch replacement (total arch group) in conjunction with ascending aorta replacement. The operative mortality rate was 22%. Total arch replacement was associated with a 33% risk of operative death, versus 15% for hemiarch ( P =0.044). Multivariable analysis found these independent predictors of operative death: age (odds ratio [OR]=1.13/yr; 95% confidence interval [CI], 1.04-1.23; P =0.002), body mass index >30 kg/m 2 (OR=9.9; 95% CI, 1.28-19; P =0.028), postoperative low cardiac output (OR=10.6; 95% CI, 1.18-25; P =0.035), and total arch replacement (OR=8.8; 95% CI, 1.39-15; P =0.021) The mean overall 5-year survival rate was 59.3% ± 5.5%, and mean 5-year freedom from distal reintervention was 95.4% ± 3.2% ( P =NS). In type A AAD, aortic arch surgery is still associated with high operative mortality rates; hemiarch replacement can be performed more safely than total arch replacement. Rates of distal aortic reoperation were not different between the 2 surgical strategies.

Methodical Design of Software Architecture Using an Architecture Design Assistant (ArchE)

DTIC Science & Technology

2005-04-01

PA 15213-3890 Methodical Design of Software Architecture Using an Architecture Design Assistant (ArchE) Felix Bachmann and Mark Klein Software...DATES COVERED 00-00-2005 to 00-00-2005 4. TITLE AND SUBTITLE Methodical Design of Software Architecture Using an Architecture Design Assistant...important for architecture design – quality requirements and constraints are most important Here’s some evidence: If the only concern is

Force delivery of NiTi orthodontic arch wire at different magnitude of deflections and temperatures: A finite element study.

PubMed

Razali, M F; Mahmud, A S; Mokhtar, N

2018-01-01

NiTi arch wires are used widely in orthodontic treatment due to its superelastic and biocompatibility properties. In brackets configuration, the force released from the arch wire is influenced by the sliding resistances developed on the arch wire-bracket contact. This study investigated the evolution of the forces released by a rectangular NiTi arch wire towards possible intraoral temperature and deflection changes. A three dimensional finite element model was developed to measure the force-deflection behavior of superelastic arch wire. Finite element analysis was used to distinguish the martensite fraction and phase state of arch wire microstructure in relation to the magnitude of wire deflection. The predicted tensile and bending results from the numerical model showed a good agreement with the experimental results. As contact developed between the wire and bracket, binding influenced the force-deflection curve by changing the martensitic transformation plateau into a slope. The arch wire recovered from greater magnitude of deflection released lower force than one recovered from smaller deflection. In contrast, it was observed that the plateau slope increased from 0.66N/mm to 1.1N/mm when the temperature was increased from 26°C to 46°C. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of cone-beam computed tomography image artifacts on the determination of dental arch measurements.

PubMed

Gamba, Thiago O; Oliveira, Matheus L; Flores, Isadora L; Cruz, Adriana D; Almeida, Solange M; Haiter-Neto, Francisco; Lopes, Sérgio L P C

2014-03-01

To compare dental plaster model (DPM) and cone-beam computed tomography (CBCT) in the measurement of the dental arches, and investigate whether CBCT image artifacts compromise the reliability of such measurements. Twenty patients were divided into two groups based on the presence or absence of metallic restorations in the posterior teeth. Both dental arches of the patients were scanned with the CBCT unit i-CAT, and DPMs were obtained. Two examiners obtained eight arch measurements on the CBCT images and DPMs and repeated this procedure 15 days later. The arch measurements of each patient group were compared separately by the Wilcoxon rank sum (Mann-Whitney U) test, with a significance level of 5% (α  =  .05). Intraclass correlation measured the level of intraobserver agreement. Patients with healthy teeth showed no significant difference between all DPM and CBCT arch measurements (P > .05). Patients with metallic restoration showed significant difference between DPM and CBCT for the majority of the arch measurements (P > .05). The two examiners showed excellent intraobserver agreement for both measuring methods with intraclass correlation coefficient higher than 0.95. CBCT provided the same accuracy as DPM in the measurement of the dental arches, and was negatively influenced by the presence of image artifacts.

Effect of antipronation foot orthosis geometry on compression of heel and arch soft tissues.

PubMed

Sweeney, Declan; Nester, Christopher; Preece, Stephen; Mickle, Karen

2015-01-01

This study aimed to understand how systematic changes in arch height and two designs of heel wedging affect soft tissues under the foot. Soft tissue thickness under the heel and navicular was measured using ultrasound. Heel pad thickness was measured when subjects were standing on a flat surface and standing on an orthosis with 4 and 8 degree extrinsic wedges and 4 mm and 8 mm intrinsic wedges (n = 27). Arch soft tissue thickness was measured when subjects were standing and when standing on an orthosis with -6 mm, standard, and +6 mm increments in arch height (n = 25). Extrinsic and intrinsic heel wedges significantly increased soft tissue thickness under the heel compared with no orthosis. The 4 and 8 degree extrinsic wedges increased tissue thickness by 28% and 27.6%, respectively, while the 4 mm and 8 mm intrinsic wedges increased thickness by 23% and 14.6%, respectively. Orthotic arch height significantly affected arch soft tissue thickness. Compared with the no orthosis condition, the -6 mm, standard, and +6 mm arch heights decreased arch tissue thickness by 9%, 10%, and 11.8%, respectively. This study demonstrates that change in orthotic geometry creates different plantar soft tissue responses that we expect to affect transmission of force to underlying foot bones.

Increased plantar force and impulse in American football players with high arch compared to normal arch

PubMed Central

Carson, Daniel W.; Myer, Gregory D.; Hewett, Timothy E.; Heidt, Robert S.; Ford, Kevin R.

2014-01-01

Background Risk of overuse injury among athletes is high due in part to repeated loading of the lower extremities. Compared to individuals with normal arch (NA) structure, those with high (HA) or low arch (LA) may be at increased risk of specific overuse injuries, including stress fractures. A high medial longitudinal arch may result in decreased shock absorbing properties due to increased rigidity in foot mechanics. While the effect of arch structure on dynamic function has been examined in straight line walking and running, the relationship between the two during multi-directional movements remains unstudied. Objective The purpose of this study was to determine if differences in plantar loading in football players occur during both walking and pivoting movements. Method Plantar loading was examined in 9 regions of the foot for 26 participants (16 NA, 10 HA). Results High arch athletes demonstrated increased maximum force in the lateral rear foot and medial forefoot, and force time integral in the medial forefoot while walking. HA athletes also demonstrated increased maximum force in the medial rear foot and medial and central forefoot during rapid pivoting. Conclusions The current findings demonstrate that loading patterns differ between football players with high and normal arch structure, which could possibly influence injury risk in this population. PMID:23141809

Mandibular arch form: the relationship between dental and basal anatomy.

PubMed

Ronay, Valerie; Miner, R Matthew; Will, Leslie A; Arai, Kazuhito

2008-09-01

We investigated mandibular dental arch form at the levels of both the clinically relevant application points of the orthodontic bracket and the underlying anatomic structure of the apical base. The correlation of both forms was evaluated and examined to determine whether the basal arch could be used to derive a standardized clinical arch form. Thirty-five mandibular dental casts (skeletal and dental Class I) were laser scanned, and a 3-dimensional virtual model was created. Two reference points (FA, the most prominent part of the central lobe on each crown's facial surface, and WALA, a point at the height of the mucogingival junction) were selected for each tooth from the right to the left first molars. The FA and WALA arch forms were compared, and the distances between corresponding points and intercanine and intermolar widths were analyzed. Both arch forms were highly individual and the tooth values scattered. Nevertheless, a highly significant relationship between the FA and WALA curves was found, especially in the canine (0.75) and molar (0.87) areas. Both FA and WALA point-derived arch forms were individual and therefore could not be defined by a generalized shape. WALA points proved to be a useful representation of the apical base and helpful in the predetermination of an individualized dental arch form.

Multiflex versus superelastic: a randomized clinical trial of the tooth alignment ability of initial arch wires.

PubMed

West, A E; Jones, M L; Newcombe, R G

1995-11-01

Two arch wires commonly used for initial tooth alignment were compared with regard to their clinical effectiveness. The two arch wires tested were 0.0155-inch diameter multiple-stranded stainless steel wire (Dentaflex, Dentaurium, Optident, Yorkshire, England) and 0.014-inch diameter nickel-titanium alloy wire (NiTi, ORMCO Co., Monrovia, Calif.). Consecutive patients attending an orthodontic clinic for routine placement of a fixed appliance were randomly assigned one of these two initial arch wires. Good quality alginate impressions of the appropriate dental arch were taken before arch wire placement and also at the subsequent appointment, which was, on average, 6 weeks later. Seventy-four arches were used in this study. The degree of tooth alignment achieved for each wire type was compared with a Reflex Microscope (Reflex Measurement Ltd., Butleigh, England) to make detailed measurements on the resultant casts. The degree of initial alignment achieved with the two wires was similar over this 6-week period. However, some differences were found for the lower labial segment where the interbracket span is usually reduced and where the superelastic nickel-titanium wire was found to give improved alignment. No threshold of crowding was found where one arch wire performed better than the other.

SOFIA/FORCAST Observations of the Arched Filamentary Region in the Galactic Center

NASA Astrophysics Data System (ADS)

Hankins, Matthew; Lau, Ryan M.; Morris, Mark; Herter, Terry L.

2016-06-01

Abstract: We present 19.7, 25.2, 31.5, and 37.1 μm maps of the Thermal Arched Filament region in the Galactic Center taken with the Faint Object Infrared Camera for the SOFIA Telescope (FORCAST) with an angular resolution of 3.2-3.8". We calculate the integrated infrared luminosity of the Arched Filaments and show that they are consistent with being heated by the nearby Arches cluster. Additionally, using our observations, we infer dust temperatures (75 - 90 K) across the Arched Filaments which are remarkably consistent over large spatial scales (˜ 25 pc). We discuss the possible geometric effects needed to recreate this temperature structure. Additionally, we compare the observed morphology of the Arches in the FORCAST maps with the Paschen-α emission in the region to study what fraction of the infrared emission may be coming from dust in the HII region versus the PDR beneath it. Finally, we use Spitzer/IRAC 8 μm data to look for spatial variations in PAH abundance in the rich UV environment of the young (~2-4 Myr) and massive Arches cluster.

Double aortic arch presenting with a foreign object in the oesophagus: a case report and imaging diagnosis.

PubMed

Yang, Xiuzhen; Ye, Jingjing; Gao, Zhan

2017-10-01

In this article, we report a rare case of double aortic arch. The case presented initially with a foreign object in the oesophagus. The patient was a 2-year-old boy, who was referred with primary symptoms of tussis (15 days) and emesis (2 days). He had a history of ingesting a coin. Routine chest X-ray indicated a rounded, metal foreign object in the upper oesophagus. A half-Yuan coin was removed by gastroduodenoscopy. Echocardiographic imaging suggested that the patient had double aortic arch, which was subsequently diagnosed by CT angiography with three-dimensional reconstruction. The right subclavian artery arose from the right loop of the double aortic arch. The left subclavian artery as well as left and right common carotid arteries had distinct origins from the left aortic arch. Imaging also indicated atresia of the distal left arch. The patient underwent corrective surgery and made a full recovery. Despite the rarity, double aortic arch should be considered when patients present with a foreign object in the oesophagus. Echocardiography and CT angiography can inform the diagnosis.

Childhood constipation is not associated with characteristic fingerprint patterns

PubMed Central

Jackson, C; Anderson, B; Jaffray, B

2003-01-01

Background: It has been suggested that there is an association between simple arch fingerprint patterns and severe childhood constipation. If real, this association might be useful to predict which children have a poor prognosis. Aim: To see how many severely constipated children have simple arches, compared to non-constipated controls and their first degree relatives. Methods: Fingerprints were classified by two blinded assessors in 30 children requiring surgery for refractory constipation, and 30 children with appendicitis, and the first degree relatives of both groups. Colonic transit times and clinical outcomes were also evaluated among constipated children. Results: At least one simple arch was found in similar numbers of constipated children (13%) and their families (16%), and control children (7%) and their families (13%). Arch positivity was commoner among relatives of arch positive (6/6) than arch negative children (14/54), regardless of bowel history. Arch positivity did not identify children with prolonged transit times, nor those who required colectomy. Conclusions: Fingerprint patterns are not associated with severe childhood constipation, do not aid their management, and do not support a genetic aetiology for this problem. PMID:14670772

Slow relaxation dynamics of clogs in a vibrated granular silo.

PubMed

Guerrero, B V; Pugnaloni, L A; Lozano, C; Zuriguel, I; Garcimartín, A

2018-04-01

We experimentally explore the vibration-induced unclogging of arches halting the flow in a two-dimensional silo. The endurance of arches is determined by carrying out a survival analysis of their breaking times. By analyzing the dynamics of two morphological variables, we demonstrate that arches evolve toward less regular structures and it seems that there may exist a certain degree of irregularity that the arch reaches before collapsing. Moreover, we put forward that σ (the standard deviation of all angles between consecutive beads) describes faithfully the morphological evolution of the arch. Focusing on long-lasting arches, we study σ calculating its two-time autocorrelation function and its mean-squared displacement. In particular, the apparent logarithmic increase of the correlation and the decrease of the mean-squared displacement of σ when the waiting time is increased reveal a slowing down of the dynamics. This behavior is a clear hallmark of aging phenomena and confirms the lack of ergodicity in the unclogging dynamics. Our findings provide new insights on how an arch tends to destabilize and how the probability that it breaks with a long sustained vibration decreases with time.

Slow relaxation dynamics of clogs in a vibrated granular silo

NASA Astrophysics Data System (ADS)

Guerrero, B. V.; Pugnaloni, L. A.; Lozano, C.; Zuriguel, I.; Garcimartín, A.

2018-04-01

We experimentally explore the vibration-induced unclogging of arches halting the flow in a two-dimensional silo. The endurance of arches is determined by carrying out a survival analysis of their breaking times. By analyzing the dynamics of two morphological variables, we demonstrate that arches evolve toward less regular structures and it seems that there may exist a certain degree of irregularity that the arch reaches before collapsing. Moreover, we put forward that σ (the standard deviation of all angles between consecutive beads) describes faithfully the morphological evolution of the arch. Focusing on long-lasting arches, we study σ calculating its two-time autocorrelation function and its mean-squared displacement. In particular, the apparent logarithmic increase of the correlation and the decrease of the mean-squared displacement of σ when the waiting time is increased reveal a slowing down of the dynamics. This behavior is a clear hallmark of aging phenomena and confirms the lack of ergodicity in the unclogging dynamics. Our findings provide new insights on how an arch tends to destabilize and how the probability that it breaks with a long sustained vibration decreases with time.

Use of 3D printer technology to facilitate surgical correction of a complex vascular anomaly with esophageal entrapment in a dog.

PubMed

Dundie, A; Hayes, G; Scrivani, P; Campoy, L; Fletcher, D; Ash, K; Oxford, E; Moïse, N S

2017-04-01

A 10 week old female intact Staffordshire terrier was presented with a total of five congenital cardio-thoracic vascular anomalies consisting of a patent ductus arteriosus (PDA) with an aneurysmic dilation, pulmonic stenosis, persistent right aortic arch, aberrant left subclavian artery and persistent left cranial vena cava. These abnormalities were identified with a combination of echocardiogram and computed tomography angiography (CTA). The abnormalities were associated with esophageal entrapment, regurgitation, and volume overload of the left heart with left atrial and ventricular enlargement. A 2 cm diameter aneurysmic dilation at the junction of the PDA, right aortic arch and aberrant left subclavian artery presented an unusual surgical challenge and precluded simple circumferential ligation and transection of the structure. A full scale three dimensional model of the heart and vasculature was constructed from the CTA and plasma sterilized. The model was used preoperatively to facilitate surgical planning and enhance intraoperative communication and coordination between the surgical and anesthesia teams. Intraoperatively the model facilitated spatial orientation, atraumatic vascular dissection, instrument sizing and positioning. A thoracoabdominal stapler was used to close the PDA aneurysm prior to transection. At the four-month postoperative follow-up the patient was doing well. This is the first reported application of new imaging and modeling technology to enhance surgical planning when approaching correction of complex cardiovascular anomalies in a dog. Copyright © 2016 Elsevier B.V. All rights reserved.

Hypoxic cardiorespiratory reflexes in the facultative air-breathing fish jeju (Hoplerythrinus unitaeniatus): role of branchial O2 chemoreceptors.

PubMed

Lopes, Jane Mello; Boijink, Cheila de Lima; Florindo, Luiz Henrique; Leite, Cleo Alcantara Costa; Kalinin, Ana Lúcia; Milsom, William K; Rantin, Francisco Tadeu

2010-08-01

In one series of experiments, heart frequency (f (H)), blood pressure (P (a)), gill ventilation frequency (f ( R )), ventilation amplitude (V (AMP)) and total gill ventilation (V (TOT)) were measured in intact jeju (Hoplerythrinus unitaeniatus) and jeju with progressive denervation of the branchial branches of cranial nerves IX (glossopharyngeal) and X (vagus) without access to air. When these fish were submitted to graded hypoxia (water PO(2) approximately 140, normoxia to 17 mmHg, severe hypoxia), they increased f ( R ), V (AMP), V (TOT) and P (a) and decreased f (H). In a second series of experiments, air-breathing frequency (f (RA)), measured in fish with access to the surface, increased with graded hypoxia. In both series, bilateral denervation of all gill arches eliminated the responses to graded hypoxia. Based on the effects of internal (caudal vein, 150 microg NaCN in 0.2 mL saline) and external (buccal) injections of NaCN (500 microg NaCN in 1.0 mL water) on f (R), V (AMP), V (TOT), P (a) and f (H) we conclude that the O(2) receptors involved in eliciting changes in gill ventilation and associated cardiovascular responses are present on all gill arches and monitor the O(2) levels of both inspired water and blood perfusing the gills. We also conclude that air breathing arises solely from stimulation of branchial chemoreceptors and support the hypothesis that internal hypoxaemia is the primary drive to air breathing.

Load rating of Bibb Graves Concrete Arch Bridge.

DOT National Transportation Integrated Search

2014-07-01

To assess the strength of the Bibb Graves Concrete Arch Bridge, the Alabama Department of Transportation sponsored an : investigation by Auburn University. In one of the spans, the arches are experiencing severe longitudinal cracking from Alkali-Sili...

Comparative Numerical Analysis of Different Strengthening Systems of Historical Brick Arches

NASA Astrophysics Data System (ADS)

Zielińska, M.

2017-05-01

The article presents a comparative numerical analysis of various ways to strengthen historical brick arches. Five ways of strengthening brick arches with steel tie-rods have been proposed. Two of these involve the use of braces wrapped around pillars supporting the arch connected with a tie-rod; the other two ways involve the use of the tie-rods with welded metal sheets of different sizes; the latter involves the use of a tie-rod glued with the use of an epoxy adhesive. The collected data were compared with the reference model of the arch left without any interference. The results make it possible to evaluate the effectiveness of the methods by comparing displacements in the vertical and horizontal direction and stresses. The article indicates the direction of proper planning and design of the arch strengthening in brick structures in historical buildings.

Coexistence of bilateral first and second branchial arch anomalies

PubMed Central

Thakur, J S; Shekar, Vidya; Saluja, Manika; Mohindroo, N K

2013-01-01

Branchial arch anomalies are one of the most common congenital anomalies that are usually unilateral and bilateral presentation is rare. The simultaneous presence of bilateral second branchial arch anomalies along with bilateral first arch anomalies is extremely rare, with only three such cases reported in the literature. We present two non-syndromic cases of coexisting bilateral first and second arch anomalies. Developmental anomalies of the branchial apparatus account for 17% of all paediatric cervical masses and are the most common type of congenital cervical mass. They usually present in the paediatric age group. About 96–97% of these anomalies are unilateral. Bilateral presentation is seen in 2–3% having a strong familial association. Congenital syndromes also have been associated with first and second branchial arch anomalies. Thorough clinical examination and investigations should be done to rule out these syndromes. PMID:23580675

A Rare Finding of the Superficial Palmar Arch-Developmental and Clinical Significance

PubMed Central

Saxena, Alok; Agarwal, Kishore Kumar; Ray, Biswabina; Pyrtuh, Samuel

2013-01-01

The ulnar artery provides a major blood supply to the hand in the form of the superficial palmar arch, with the assistance of the radial artery. A rare pattern of the superficial palmar arch was observed in a formalin fixed, male cadaveric left hand. The ulnar artery was only involved in the formation of this arch, which provided three common palmar digital arteries which ran into the second, third and the fourth spaces between the corresponding digits and one proper palmar digital artery which ran along the ulnar side of the little finger. The main trunk of the ulnar artery bifurcated to supply the thumb and the index finger. The superficial branch of the radial artery did not participate in the arch formation. The arch was completed by the radial artery proper on the dorsolateral surface of the hand, after joining the point of bifuracation of the ulnar artery. PMID:23730652

Effect of lip bumpers on mandibular arch dimensions.

PubMed

Hashish, Dena Ibrahim; Mostafa, Yehya Ahmed

2009-01-01

The aim of this systematic review was to examine the effects of lip bumper therapy on mandibular arch dimensions. A literature survey of PubMed, EMBASE, Cochrane Central, and Cochrane Database of Systematic Reviews (www.cochrane.org) was conducted from December 1968 to January 2007. Human studies, randomized clinical trials, prospective and retrospective studies, and studies discussing the effect of lip bumpers on the arch and teeth were included. Two reviewers independently selected and extracted the data. Of the 52 studies found in the search, only 1 met the inclusion criteria. The results showed increases in arch dimensions that included an increase in arch length. This was attributed to incisor proclination, distalization, and distal tipping of the molars. There was also an increase in the arch width seen in the intercanine and deciduous intermolar and premolar distances. The long-term stability of the effects of the lip bumper need to be elucidated.

Association of X-ray arches with chromospheric neutral lines

NASA Technical Reports Server (NTRS)

Mcintosh, P. S.; Krieger, A. S.; Nolte, J. T.; Vaiana, G.

1976-01-01

Daily maps of magnetic neutral lines derived from H-alpha observations have been superimposed on solar X-ray images for the period from June 15 to 30, 1973. Nearly all X-ray-emitting structures consist of systems of arches covering chromospheric neutral lines. Areas of low emissivity, coronal holes, appear as the areas between arcades of arches. The presence of a coronal hole, therefore, is determined by the spacing between neutral lines and the scale of the arches over those neutral lines. X-ray emissivity on the solar disk extends from neutral lines in proportion to the vertical and horizontal scale of the arches over those neutral lines. Increasing scale of arches corresponds with increasing age of magnetic fields associated with the neutral line. All X-ray filament cavities coincided with neutral lines, but filaments appeared under cavities for only part of their length and for only a fraction of the disk passage.

Arch bar stabilization of endotracheal tubes in children with facial burns.

PubMed

Perrotta, V J; Stern, J D; Lo, A K; Mitra, A

1995-01-01

Endotracheal tube stabilization in children with facial burns can be difficult. Several methods rely on straps or complex devices that apply undesirable pressure to the face, potentially destroying skin grafts and making wound care difficult. Techniques that rely on a single wire or suture can be unreliable. Presented here is the arch bar method of endotracheal tube stabilization, which appears to be free of these problems. This method employs a standard dental arch bar secured to four maxillary teeth with 24-gauge stainless steel wire. The endotracheal tube is anchored to the arch bar with two pieces of wire or suture material. The arch bar method of endotracheal tube stabilization was used on three patients in the burn center at St. Christopher's Hospital for Children. Wound care and successful skin grafting were performed without difficulty. No complications related to the arch bars occurred.

The patent ductus arteriosus in term infants, children, and adults.

PubMed

Schneider, Douglas J

2012-04-01

During fetal life, the ductus arteriosus is a normal and essential structure that connects the pulmonary artery to the distal aortic arch, permitting right ventricular ejection into the aorta. After birth, with commencement of pulmonary blood flow and a 2-ventricle circulation, a variety of physiological and biochemical signals normally result in complete closure of the ductus. Persistent patency of the ductus arteriosus may impair systemic cardiac output and result in deleterious effects on the cardiovascular system and lungs. Although surgery is still the treatment of choice for most premature infants with patent ductus arteriosus (PDA), transcatheter techniques have largely supplanted surgery for closure of PDA in children and adults. This article is a review of the PDA in term infants, children, and adults, with focus on the clinical manifestations and management. Copyright © 2012 Elsevier Inc. All rights reserved.

Analysis of 6-minute walk test safety in pre-heart transplantation patients.

PubMed

Cipriano, Gerson; Yuri, Darlene; Bernardelli, Graziella França; Mair, Vanessa; Buffolo, Enio; Branco, João Nelson Rodrigues

2009-04-01

The 6-minute walk test (6WT) has been used as a means of assessment of the functional capacity, clinical staging and cardiovascular prognosis. Its safety and metabolic impact have not been frequently described in the literature, especially in patients with severe heart failure with clinical indication for cardiovascular transplantation. To evaluate the occurrence of arrhythmias and cardiovascular changes during 6WT. To correlate 6WT performance with clinical staging and cardiovascular prognosis. Twelve patients, 10 of whom males, aged 52 +/- 8 years were evaluated at baseline. 6WT was performed with telemetry electrocardiography, vital signs and lactate monitoring. The patients were followed-up for 12 months. The patients walked 399.4+/-122.5 (D, m), reaching a perceived exertion (PE) of 14.3+/-1.5 and a 34% baseline heart rate variation. Two patients presented more severe pre-6WT arrhythmia which did not worsen with the exercise, four patients presented a significant increase of blood lactate levels (>5 mmol/dl), and three interrupted the test. The distance walked correlated with the ejection fraction (%) and functional class (NYHA). After 12-month follow-up, three patients died and seven were rehospitalized for cardiac decompensation. The D/PE ratio and 2-minute heart rate recovery (HRR2, bpm) were lower in the death group. The clinical and electrocardiographic behaviors suggest that the method is safe, but it may be considered too strenuous for some patients with severe heart failure. Variables related to 6WT performance may be associated with the one-year follow-up mortality.

Cardiovascular dysfunction following spinal cord injury

PubMed Central

Partida, Elizabeth; Mironets, Eugene; Hou, Shaoping; Tom, Veronica J.

2016-01-01

Both sensorimotor and autonomic dysfunctions often occur after spinal cord injury (SCI). Particularly, a high thoracic or cervical SCI interrupts supraspinal vasomotor pathways and results in disordered hemodynamics due to deregulated sympathetic outflow. As a result of the reduced sympathetic activity, patients with SCI may experience hypotension, cardiac dysrhythmias, and hypothermia post-injury. In the chronic phase, changes within the CNS and blood vessels lead to orthostatic hypotension and life-threatening autonomic dysreflexia (AD). AD is characterized by an episodic, massive sympathetic discharge that causes severe hypertension associated with bradycardia. The syndrome is often triggered by unpleasant visceral or sensory stimuli below the injury level. Currently the only treatments are palliative – once a stimulus elicits AD, pharmacological vasodilators are administered to help reduce the spike in arterial blood pressure. However, a more effective means would be to mitigate AD development by attenuating contributing mechanisms, such as the reorganization of intraspinal circuits below the level of injury. A better understanding of the neuropathophysiology underlying cardiovascular dysfunction after SCI is essential to better develop novel therapeutic approaches to restore hemodynamic performance. PMID:27073353

Maintenance of longitudinal foot arch after different mid/hind-foot arthrodesis procedures in a cadaveric model.

PubMed

Chen, Yanxi; Zhang, Kun; Qiang, Minfei; Hao, Yini

2014-02-01

Currently, the optimal treatment of flatfoot remains inconclusive. Our objectives were to understand the effect of different arthrodeses on maintenance of foot arch and provide experimental basis for rational selection in treatment of flatfoot. Sixteen fresh-frozen cadaver feet amputated above the ankle along with a section of leg were studied from ten males and six females. We used standard clinical techniques and hardware for making the arthrodeses. Plantar pressure in the medial and lateral longitudinal arch distribution was measured with a plantar pressure mapping system under different loading conditions. Values of plantar pressure reaction, mean and maximum dynamic peak pressure between all group pairs were statistically significant (P<0.05). The plantar pressure reaction appeared at the load of 960 N in the medial arch of the unoperated foot, compared with 1080 N after subtalar arthrodesis, 1200 N after talonavicular arthrodesis, 1080 N after calcaneocuboid arthrodesis, 1320 N after double arthrodesis, and 1560 N after triple arthrodesis. The plantar pressure reaction appeared at the load of 360 N in the lateral arch of the unoperated foot, compared with 600 N after subtalar arthrodesis, 600 N after talonavicular arthrodesis, 840 N after calcaneocuboid arthrodesis, 960 N after double arthrodesis, and 1440 N after triple arthrodesis. The triple arthrodesis provided the highest support to both arches; the double arthrodesis appeared to be similar to talonavicular arthrodesis in supporting the medial arch and similar to calcaneocuboid arthrodesis in supporting the lateral arch; subtalar arthrodesis was less effective in supporting both arches. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of intraoral scanning and conventional impression techniques using 3-dimensional superimposition.

PubMed

Rhee, Ye-Kyu; Huh, Yoon-Hyuk; Cho, Lee-Ra; Park, Chan-Jin

2015-12-01

The aim of this study is to evaluate the appropriate impression technique by analyzing the superimposition of 3D digital model for evaluating accuracy of conventional impression technique and digital impression. Twenty-four patients who had no periodontitis or temporomandibular joint disease were selected for analysis. As a reference model, digital impressions with a digital impression system were performed. As a test models, for conventional impression dual-arch and full-arch, impression techniques utilizing addition type polyvinylsiloxane for fabrication of cast were applied. 3D laser scanner is used for scanning the cast. Each 3 pairs for 25 STL datasets were imported into the inspection software. The three-dimensional differences were illustrated in a color-coded map. For three-dimensional quantitative analysis, 4 specified contact locations(buccal and lingual cusps of second premolar and molar) were established. For twodimensional quantitative analysis, the sectioning from buccal cusp to lingual cusp of second premolar and molar were acquired depending on the tooth axis. In color-coded map, the biggest difference between intraoral scanning and dual-arch impression was seen (P<.05). In three-dimensional analysis, the biggest difference was seen between intraoral scanning and dual-arch impression and the smallest difference was seen between dual-arch and full-arch impression. The two- and three-dimensional deviations between intraoral scanner and dual-arch impression was bigger than full-arch and dual-arch impression (P<.05). The second premolar showed significantly bigger three-dimensional deviations than the second molar in the three-dimensional deviations (P>.05).

Evaluation of arch width variations among different skeletal patterns in South Indian population.

PubMed

Prasad, Mandava; Kannampallil, Senny Thomas; Talapaneni, Ashok Kumar; George, Suja Ani; Shetty, Sharath Kumar

2013-01-01

Anterior cranial base can be taken as a reference line (SN) to determine the steepness of mandibular plane. Subjects with high mandibular plane angle tend to have a long face and one with low MP-SN angle has a shorter face. This study was done to investigate if dental arch widths correlated with vertical facial types and if there are any differences in arch widths between untreated male and female adults in South Indian population. Lateral cephalogram and dental casts were obtained from 180 untreated South Indian adults (90 males and 90 females) above 18 year old with no cross bite, minimal crowding and spacing. The angle between the anterior cranial base and the mandibular plane was measured on lateral cephalogram of each patient. Dental casts were used to obtain comprehensive dental measurements including maxillary and mandibular inter canine, inter premolar and inter molar widths, as well as amount of crowding or spacing. The results showed that male arch widths were significantly larger than those of females (P < 0.05) and there was a significant decrease in inter arch width as the MP-SN angle increased in untreated adult South Indian population. The results obtained in our study when compared with studies done in other population groups showed that there is difference in inter arch widths according to ethnicity and race. It was concluded that the dental arch width is associated with gender, race and vertical facial morphology. Thus using individualized arch wires according to each patient's pre treatment arch form and width is suggested during orthodontic treatment.

In vivo Study of the Accuracy of Dual-arch Impressions.

PubMed

de Lima, Luciana Martinelli Santayana; Borges, Gilberto Antonio; Junior, Luiz Henrique Burnett; Spohr, Ana Maria

2014-06-01

This study evaluated in vivo the accuracy of metal (Smart®) and plastic (Triple Tray®) dual-arch trays used with vinyl polysiloxane (Flexitime®), in the putty/wash viscosity, as well as polyether (Impregum Soft®) in the regular viscosity. In one patient, an implant-level transfer was screwed on an implant in the mandibular right first molar, serving as a pattern. Ten impressions were made with each tray and impression material. The impressions were poured with Type IV gypsum. The width and height of the pattern and casts were measured in a profile projector (Nikon). The results were submitted to Student's t-test for one sample (α = 0.05). For the width distance, the plastic dual-arch trays with vinyl polysiloxane (4.513 mm) and with polyether (4.531 mm) were statistically wider than the pattern (4.489 mm). The metal dual-arch tray with vinyl polysiloxane (4.504 mm) and with polyether (4.500 mm) did not differ statistically from the pattern. For the height distance, only the metal dual-arch tray with polyether (2.253 mm) differed statistically from the pattern (2.310 mm). The metal dual-arch tray with vinyl polysiloxane, in the putty/wash viscosities, reproduced casts with less distortion in comparison with the same technique with the plastic dual-arch tray. The plastic or metal dual-arch trays with polyether reproduced cast with greater distortion. How to cite the article: Santayana de Lima LM, Borges GA, Burnett LH Jr, Spohr AM. In vivo study of the accuracy of dual-arch impressions. J Int Oral Health 2014;6(3):50-5.

Comparison of intraoral scanning and conventional impression techniques using 3-dimensional superimposition

PubMed Central

Rhee, Ye-Kyu

2015-01-01

PURPOSE The aim of this study is to evaluate the appropriate impression technique by analyzing the superimposition of 3D digital model for evaluating accuracy of conventional impression technique and digital impression. MATERIALS AND METHODS Twenty-four patients who had no periodontitis or temporomandibular joint disease were selected for analysis. As a reference model, digital impressions with a digital impression system were performed. As a test models, for conventional impression dual-arch and full-arch, impression techniques utilizing addition type polyvinylsiloxane for fabrication of cast were applied. 3D laser scanner is used for scanning the cast. Each 3 pairs for 25 STL datasets were imported into the inspection software. The three-dimensional differences were illustrated in a color-coded map. For three-dimensional quantitative analysis, 4 specified contact locations(buccal and lingual cusps of second premolar and molar) were established. For twodimensional quantitative analysis, the sectioning from buccal cusp to lingual cusp of second premolar and molar were acquired depending on the tooth axis. RESULTS In color-coded map, the biggest difference between intraoral scanning and dual-arch impression was seen (P<.05). In three-dimensional analysis, the biggest difference was seen between intraoral scanning and dual-arch impression and the smallest difference was seen between dual-arch and full-arch impression. CONCLUSION The two- and three-dimensional deviations between intraoral scanner and dual-arch impression was bigger than full-arch and dual-arch impression (P<.05). The second premolar showed significantly bigger three-dimensional deviations than the second molar in the three-dimensional deviations (P>.05). PMID:26816576

4. 3/4 VIEW OF ARCH OVER ROADWAY AT SOUTH END ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. 3/4 VIEW OF ARCH OVER ROADWAY AT SOUTH END OF SPAN, LOOKING SW, SHOWING RIBBED ARCH CONSTRUCTION. - Philadelphia & Reading Railroad, Peacock's Lock Viaduct, Spanning Schuykill River at Reading Railroad, Reading, Berks County, PA

5. TOP OF ARCH AND VIADUCT. NOTE THAT STONES OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. TOP OF ARCH AND VIADUCT. NOTE THAT STONES OF ARCH HAVE BEEN DRAFTED FINISH AROUND THE EDGE) AND THE KEYSTONE HAS BEEN ROUGHLY POINTED. - Valley Railroad, Folly Mills Creek Viaduct, Interstate 81, Staunton, Staunton, VA

Recurrent thyroid abscess - Is it a fourth branchial archanomaly?

PubMed

Desai, A A; Pandya, V K; Chougule, Sachin; Nair, Unnikrishnnan

2006-04-01

Branchial fistulae are of congenital origin(6) and consists of skin lined tract opening internally at junction of cartilaginous and bony meatus in case of 1(st) arch anomaly, tonsillar fossa in case of 2(nd) arch, while 3(rd) and 4(th) arch sinuses have internal opening at level of pyriform sinus or below. A complete tract of 3(rd) or 4(th) arch fistulae is yet to be described. Fourth arch fistulae(1) have a distinct clinical pattern of internal opening at pyriform apex, are left sided and associated with suppurative thyroiditis(3), they manifest at a younger age and treatment involves excision of tract with ipsilateral thyroid lobectomy.

Probabilistic and statistical relationships between number of vehicles and number of visitors at a geologic site in a National Park

USGS Publications Warehouse

Crovelli, R.A.

1997-01-01

The National Park Service needs to establish in all of the national parks how large the parking lots should be in order to enjoy and presence our natural resources, for example, in the Delicate Arch in the Arches National Park. Probabilistic and statistical relationships were developed between the number of vehicles (N) at one time in the Wolfe Ranch parking lot and the number of visitors (X) at Delicate Arch 1.5 miles away in the Arches National Park, southeastern Utah. The value of N is determined such that 30 or more visitors are at the arch only 10% of the time.

Aneurysm of an Aberrant Right Subclavian Artery Successfully Excluded by a Thoracic Aortic Stent Graft with Supra-aortic Bypass of Three Arch Vessels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munneke, Graham J.; Loosemore, Thomas M.; Belli, Anna-Maria

2005-06-15

An aberrant right subclavian artery (ARSA) arising from a left-sided aortic arch is the fourth most common aortic arch anomaly. Aneurysmal dilatation of the ARSA requires treatment because of the associated risk of rupture. We present a case where supra-aortic bypass of the arch vessels was performed to facilitate exclusion of the aneurysm by a thoracic aortic stent graft.

The deep plantar arch in humans: constitution and topography.

PubMed

Gabrielli, C; Olave, E; Mandiola, E; Rodrigues, C F; Prates, J C

2001-01-01

The integrity of the various structures within the feet depends on their blood supply. Lesions of the feet often require revascularization, which if successful avoids the need for amputation. To provide greater anatomical detail to aid vascular surgery and imaging, the anatomy and constitution of the deep plantar arch was studied in 50 adult cadaveric feet. The arteries of the foot were injected with red neoprene latex and dissected under magnification. The deep plantar arch, present in all feet, was the result of anastomosis between the deep plantar artery and the deep branch of the lateral plantar artery. The deep plantar artery was predominant in 72% of specimens (Type I arches) and the lateral plantar artery in 22% (Type II), with the contribution being equal in 6% (Type III). The medial plantar artery contributed to the medial segment of the deep plantar arch by its deep branch in 12% of specimens. The distance between the deep plantar arch and each interdigital commissure was generally constant, averaging 29% of total foot length. The deep plantar arch was located in the middle third of the foot in all specimens, being in the distal part of this third in 90%. The deep plantar arch is, therefore formed mainly by the deep plantar artery, a branch of the dorsal artery of foot; its location can be estimated if foot length is known.

Effect of Obesity Level on the Longitudinal Arch in 7- to 12-Year-Old Rural and Urban Children.

PubMed

Woźniacka, Renata; Bac, Aneta; Matusik, Stanisław

2015-11-01

We sought to evaluate the influence of obesity level on the medial longitudinal arch (MLA) of the foot in 7- to 12-year-old children. The study group consisted of 925 children (450 girls and 475 boys). All of the children were subjected to podoscopic foot examination and measurement of weight, height, three skinfolds, fat weight, and fat-free body weight. The most common type of MLA was high-arched foot, which was observed in the left foot of 523 children (56.5%) and in the right foot in 592 children (64%). In almost all of the age groups, high-arched foot was the most common disorder. High-arched foot was more common in girls than in boys, and boys displayed a higher percentage of flatfoot. Also, sex-related differences were more prominent in urban children. There was a strongly positive correlation between obesity level and MLA in the examined group. These results suggest that the type of foot arch is influenced by parameters such as age, sex, and obesity level. High-arched foot seemed to be the most frequent pathologic abnormality in the examined group, and flatfoot, which was predominant in boys and obese children, diminished with age. High-arched foot was a more common MLA type than flatfoot regardless of obesity level assessed on the basis of body mass index and sum of three skinfolds.

Infant orthopedics has no effect on maxillary arch dimensions in the deciduous dentition of children with complete unilateral cleft lip and palate (Dutchcleft).

PubMed

Bongaarts, Catharina A M; van 't Hof, Martin A; Prahl-Andersen, Birte; Dirks, Iris V; Kuijpers-Jagtman, Anne M

2006-11-01

Evaluation of the effect of infant orthopedics on maxillary arch dimensions in the deciduous dentition in patients with unilateral cleft lip and palate. Prospective two-arm randomized controlled clinical trial with three participating cleft palate centers. Cleft palate centers of the Radboud University Nijmegen Medical Center, Academic Center of Dentistry Amsterdam, and University Medical Center Rotterdam, the Netherlands. Children with complete unilateral cleft lip and palate (n = 54) were included. Patients were randomly divided into two groups. Half of the patients (IO+) had a presurgical orthopedic plate until surgical closure of the soft palate at the age of 52 weeks; the other half (IO-) did not undergo presurgical orthopedics. Maxillary arch dimensions were assessed on dental casts at 4 and 6 years of age with measurements for arch width, arch depth, arch length, arch form, and the vertical position of the lesser segment. Contact and collapse were assessed also. There were no clinically significant differences found between IO+ and IO- for any of the variables. Infant orthopedics had no observable effect on the maxillary arch dimensions or on the contact and collapse scores in the deciduous dentition at the ages of 4 and 6 years. Considering the Dutchcleft results to date, there is no need to perform infant orthopedics for unilateral cleft lip and palate patients.

The long-term outcomes of partial arch repair using the frozen elephant trunk technique for distal arch aortic aneurysm.

PubMed

Sueda, Taijiro; Takahashi, Shinya; Katayama, Keijiro; Morita, Shohei; Watanabe, Masazumi; Kurosaki, Tatsuya

2018-06-22

The purpose of this study was to evaluate the long-term results of partial arch repair using the frozen elephant trunk (FET) technique for distal arch aortic aneurysm and to examine the late complications. Thirty-eight patients with true distal arch aortic aneurysms were repaired with FET introduced through an incision in the proximal arch aorta. Follow-up computed tomography was performed every 6 or 12 months in 36 surviving patients. The maximum dimension of the excluded aneurysmal space was measured to determine whether the aneurysmal space had decreased or disappeared. Late complications were also evaluated during the long-term follow-up. There was 1 hospital death (2.6%) and 1 (2.6%) case of paraplegia. There were 2 late sudden deaths (5.2%) thought to be due to aneurysm rupture and arrhythmia. Postoperative serial-computed tomography showed shrinkage of the excluded aneurysmal space in 33 of 36 patients. Late aneurysmal formation occurred in the anastomotic site in three patients. One patient underwent thoracic endovascular stent grafting 10 years after surgery, 1 patient had total arch replacement 9 years after surgery, and 1 died due to rupture. Frozen elephant trunk was found to be a useful alternative for treating true distal arch aortic aneurysm. However, we must be alert for late aneurysmal formation at the incision site.

Advantages of the L-incision approach comprising a combination of left anterior thoracotomy and upper half-median sternotomy for aortic arch aneurysms.

PubMed

Oishi, Yasuhisa; Sonoda, Hiromichi; Tanoue, Yoshihisa; Nishida, Takahiro; Tokunaga, Shigehiko; Nakashima, Atsuhiro; Shiokawa, Yuichi; Tominaga, Ryuji

2011-09-01

Although surgical outcomes of total arch replacement have improved, the strategy for extended arch aneurysms remains controversial. We have applied the L-incision approach (combination of left anterior thoracotomy and upper half-median sternotomy) for total arch replacement for single-stage repair of extensive arch aneurysms. We retrospectively reviewed the operative outcomes of patients who underwent total arch or extended total arch replacement for degenerative aneurysms from 1999 to 2010. Operations were performed via median sternotomy in 47 patients (M group) and the L-incision approach was used in 38 patients (L group). Through the L-incision approach, we were able to complete distal anastomosis below the pulmonary hilus. The L-incision approach has advantages of reducing selective antegrade cerebral perfusion and lower body circulatory arrest times compared with the M group. Recurrent laryngeal nerve palsy and renal dysfunction were less frequent in the L group than those in the M group. Respiratory dysfunction and wound infection were similar between the groups. Hospital mortalities were 5.3% in the L group and 6.4% in the M group. The L-incision approach has similar or better postoperative outcomes compared with the median sternotomy approach. This approach could be useful for single-stage extended total arch replacement with relatively low risk.

Biomechanics of longitudinal arch support mechanisms in foot orthoses and their effect on plantar aponeurosis strain.

PubMed

Kogler, G F; Solomonidis, S E; Paul, J P

1996-07-01

OBJECTIVE: The purpose of this investigation was to quantify the longitudinal arch support properties of several types of foot orthosis. DESIGN: An in vitro method that simulated 'static stance' was used to determine arch support capabilities, with plantar aponeurosis strain implemented as the performance measure. BACKGROUND: A longitudinal arch support mechanism of an orthosis resists depression of the foot's arches by transferring a portion of the load to the medial structures of the foot. Since the plantar aponeurosis is in tension when the foot is loaded, a quantifiable decrease in strain should occur with an adequate orthotic arch control mechanism. METHODS: A differential variable reluctance transducer was surgically implanted in the plantar aponeurosis of cadaveric donor limb feet (n = 7). Each specimen was mounted in an electromechanical test machine which applied a load of up to 900 N axially to the tibia. The test schedule was divided into seven test conditions: specimen barefoot; specimen with shoe and specimen with shoe and five different orthoses. RESULTS: The University of California Biomechanics Laboratory Shoe Insert and two other foot orthoses significantly decreased the strain in the plantar aponeurosis compared to the barefoot control and were considered effective arch supports (P < 0.05). The functional foot orthosis, stock orthosis, and test shoe did not effectively reduce plantar aponeurosis strain. Significant variations of time required to achieve the specified load levels were recorded among the test conditions, indicating the relative cushioning properties of the shoe/orthosis systems. CONCLUSIONS: The patterns of plantar aponeurosis strain observed in cadaveric tests suggest that certain types of orthoses are more effective than others in the support of the foot's longitudinal arches. It is suggested that to support the longitudinal arches of the foot effectively the medial surface contours of the orthosis must stabilize the apical bony structure of the foot's arch. RELEVANCE: Reducing tension in the plantar aponeurosis is an important treatment objective for orthotic management of plantar fasciitis. Therefore it is of great clinical interest to know whether the longitudinal arch support mechanism of specific foot orthoses have benefits with respect to the loading of the plantar aponeurosis.

Examining Sites of Recent Star Formation in the Galactic Center: A Closer Look at the Arched Filaments and H HII Regions

NASA Astrophysics Data System (ADS)

Hankins, Matthew; Herter, Terry; Lau, Ryan; Morris, Mark; Mills, Elisabeth

2018-01-01

In this dissertation presentation, we analyze mid-infrared imaging of the Arched Filaments and H HII regions in the Galactic center taken with the Faint Object Infrared Camera for the SOFIA Telescope (FORCAST). Examining these regions are of great interest because they provide insights on star formation in the Galactic center and the interactions massive stars have with the ISM. The Arched Filaments are a collection of molecular cloud ridges which are ionized by the nearby Arches star cluster, and give the appearance of large (~25 pc) arch-like structures. The H HII regions are a collection of HII regions just to the west of the Arches cluster (~5-15 pc). The origin of the stars powering the H HII regions is uncertain, as they may have formed in a nearby molecular cloud or could be ejected members of the Arches cluster. FORCAST observations of these regions were used to study the morphology and heating structure of the HII regions, as well as constrain their luminosities.Color-temperature maps of the Arched Filaments created with the FORCAST data reveals fairly uniform dust temperatures (~70-100 K) across the length filaments. The temperature uniformity of the clouds can be explained if they are heated by the Arches cluster but are located at a larger distance from the cluster than they appear. The density of the Arched Filaments clouds was estimated from the FORCAST data and was found to be below the threshold for tidal shearing, indicating that that the clouds will be destroyed by the strong tidal field near the Galactic center. To the west of the Arched Filaments, there is an interesting collection of HII regions, referred to as the H HII regions. These regions are likely heated by massive O/B type stars, and the morphology of the dust emission associated with these objects indicate a mixture of potential in situ formation mechanisms and interlopers. Interestingly, FORCAST imaging of the H HII regions also reveal several compact sources, which may be young embedded stars. We discuss these sources in the context of star formation scenarios in the Galactic center.

5. View northwest at the northeastmost arch of culvert inlet ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. View northwest at the northeastmost arch of culvert inlet headwall, showing high inlet vault and interior drop arch. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

21. FOREBAY; GATE MECHANISM VISIBLE IN LOWER LEFT; HEADRACE ARCH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. FOREBAY; GATE MECHANISM VISIBLE IN LOWER LEFT; HEADRACE ARCH IS IN NORTH WALL OF FOREBAY, BEHIND MASONRY ARCH IN CENTER; LOOKING NORTHEAST - Crown Roller Mill, 105 Fifth Avenue, South, West Side Milling District, Minneapolis, Hennepin County, MN

2. STONE ARCH BRIDGE. TIMBERS ON THE UPSTREAM FACE OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. STONE ARCH BRIDGE. TIMBERS ON THE UPSTREAM FACE OF THE PIER PROTECTED THE STONEWORK FROM DAMAGE FROM ICE FLOWS, BARGES, ETC. - Lockport Historic District, Stone Arch Bridge, Spanning Des Plaines River at Ninth Street, Lockport, Will County, IL

The mandibular symphysis as a starting point for the occlusal-level reconstruction of panfacial fractures with bicondylar fractures and interruption of the maxillary and mandibular arches: report of two cases.

PubMed

Pau, Mauro; Reinbacher, Knut Ernst; Feichtinger, Matthias; Navysany, Kawe; Kärcher, Hans

2014-06-01

Panfacial fractures represent a challenge, even for experienced maxillofacial surgeons, because all references for reconstructing the facial skeleton are missing. Logical reconstructive sequencing based on a clear understanding of the correlation between projection and the widths and lengths of facial subunits should enable the surgeon to achieve correct realignment of the bony framework of the face and to prevent late deformity and functional impairment. Reconstruction is particularly challenging in patients presenting with concomitant fractures at the Le Fort I level and affecting the palate, condyles, and mandibular symphysis. In cases without bony loss and sufficient dentition, we believe that accurate fixation of the mandibular symphysis can represent the starting point of a reconstructive sequence that allows successful reconstruction at the Le Fort I level. Two patients were treated in our department by reconstruction starting in the occlusal area through repair of the mandibular symphysis. Both patients considered the postoperative facial shape and profile to be satisfactory and comparable to the pre-injury situation. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Extracorporeal membrane oxygenation in children with heart disease and del22q11 syndrome: a review of the Extracorporeal Life Support Organization Registry.

PubMed

Prodhan, P; Gossett, J M; Rycus, P T; Gupta, P

2015-11-01

The study objective was to evaluate outcomes among children with del22q11 (DiGeorge) syndrome supported on ECMO for heart disease. The ELSO registry database was queried to include all children <18 years undergoing heart surgery for either common atrio-ventricular canal, tetralogy of Fallot, truncus arteriosus or transposition of the great vessels and interrupted aortic arch and requiring ECMO, from 1998-2011. The outcomes evaluated included mortality, ECMO duration and length of hospital stay in patients with del22q11 syndrome and with no del22q11 syndrome. Eighty-eight ECMO runs occurred in children with del22q11 syndrome while 2694 ECMO runs occurred in children without del22q11 syndrome. For patients with heart defects receiving ECMO, del22q11 syndrome did not confer a significant mortality risk or an increased risk of infectious complications before or while on ECMO support. Neither the duration of ECMO nor mechanical ventilation prior to ECMO deployment were prolonged in patients with del22q11 syndrome compared to the controls. © The Author(s) 2015.

Description and SEM Observations of Meloidogyne sasseri n. sp. (Nematoda: Meloidogynidae), Parasitizing Beachgrasses

PubMed Central

Handoo, Zafar A.; Huettel, Robin N.; Golden, A. Morgan

1993-01-01

Meloidogyne sasseri n. sp. is described and illustrated from American beachgrass (Ammophila breviliffulata) originally collected from Henlopen State Park and Fenwick Island near the Maryland state line in Delaware, United States (6). Its relationship to M. graminis, M. spartinae, and M. californiensis is discussed. Primary distinctive characters of the female perineal pattern were a high to rounded arch with shoulders, widely spaced lateral lines interrupting transverse striations, a sunken vulva and anus, and coarse broken striae around the anal area. Second-stage juvenile body length was 554 μm (470-550), stylet length 14 μm (13-14.5), tail length 93 μm (83-115), tapering to a finely rounded terminus. Male stylet length 20 μm (19-21.5), spicule length 33 μm (30-36). Scanning electron microscope observations provided additional details of perineal patterns and face views of the female, male, and J2 head. Wheat, rice, oat, Ammophila sp., Panicum sp., bermudagrass, zoysiagrass and St. Augustinegrass were tested as hosts. Distribution of the species was the coasts of Delaware and Maryland. The common name "beachgrass root-knot" is proposed for M. sasseri n. sp. PMID:19279820

Sleep-Disordered Breathing in Heart Failure　- A Therapeutic Dilemma.

PubMed

Haruki, Nobuhiko; Floras, John S

2017-06-23

Sleep-disordered breathing (SDB) occurs in approximately 50% of patients with reduced left ventricular ejection fraction receiving contemporary heart failure (HF) therapies. Obstructive (OSA) and central sleep apneas (CSA) interrupt breathing by different mechanisms but impose qualitatively similar autonomic, chemical, mechanical, and inflammatory burdens on the heart and circulation. Because contemporary evidence-based drug and device HF therapies have little or no mitigating effect on the acute or long-term consequences of such stimuli, there is a sound mechanistic rationale for targeting SDB to reduce cardiovascular event rates and prolong life. However, the promise of observational studies and randomized trials of small size and duration describing a beneficial effect of treating SDB in HF via positive airway pressure was not realized in 2 recent randomized outcome-driven trials: SAVE, which evaluated the cardiovascular effect of treating OSA in a cohort without HF, and SERVE-HF, which reported the results of a strategy of random allocation of minute-ventilation-triggered adaptive servo-ventilation (ASV) for HF patients with CSA. Whether effective treatment of either OSA or CSA improves the HF trajectory by reducing cardiovascular morbidity or mortality has yet to be definitively established. ADVENT-HF, designed to determine the effect of treating both CSA and non-sleepy OSA HF patients with a peak-airflow triggered ASV algorithm, could resolve this present clinical equipoise concerning the treatment of SDB.

The Effect of Arch Drop on Tibial Rotation and Tibiofemoral Contact Stress in Postpartum Women.

PubMed

Rabe, Kaitlin; Segal, Neil A; Waheed, Saphia; Anderson, Donald D

2018-04-26

Women are at greater risk for knee osteoarthritis and numerous other lower limb musculoskeletal disorders. Arch drop during pregnancy and the resultant excessive pronation of the feet may alter loading patterns and contribute to the greater prevalence of knee osteoarthritis in women. To determine the effect of arch drop on tibial rotation and tibiofemoral contact stress. Interventional study with internal control. Biomechanics laboratory. Eleven postpartum women (age 33.4 ± 5.3 years, body mass 76.1 ± 13.5 kg) who had lost arch height with pregnancy in a previous study. Subjects underwent standing computed tomography (SCT) with their knees in a 20° fixed-flexed position with and without semirigid arch supports to reconstitute prepregnancy arch height. Magnetic resonance imaging of the knee was acquired at a flexion angle equivalent to that of SCT. Bone and cartilage were manually segmented on the magnetic resonance images and segmented surfaces were registered to the 3-dimensional SCT image sets for the arch-supported and -unsupported conditions. These models were used to measure changes in tibial rotation, as well as to estimate contact stress in the medial and lateral tibiofemoral compartments, using computational methods. Change in tibial rotation and tibiofemoral contact stress with arch drop. Arch drop resulted in a mean tibial internal rotation of 0.75 ± 1.33° (P < .05). Changes in mean or peak contact stress were not detected. Arch drop causes internal tibial rotation, resulting in a shift in the tibiofemoral articulation. An associated increase in contact stress was not detected. Internal rotation of the tibia increases stress on the anterior cruciate ligament and menisci, potentially explaining the greater prevalence of knee disorders in postpartum women. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

The influence of foot orthoses on foot mobility magnitude and arch height index in adults with flexible flat feet.

PubMed

Sheykhi-Dolagh, Roghaye; Saeedi, Hassan; Farahmand, Behshid; Kamyab, Mojtaba; Kamali, Mohammad; Gholizadeh, Hossein; Derayatifar, Amir A; Curran, Sarah

2015-06-01

Flexible flat foot is described as a reduction in the height of the medial longitudinal arch and may occur from abnormal foot pronation. A foot orthosis is thought to modify and control excessive pronation and improve arch height. To compare the immediate effect of three types of orthoses on foot mobility and the arch height index in subjects with flexible flat feet. A quasi-experimental study. The dorsal arch height, midfoot width, foot mobility and arch height index were assessed in 20 participants with flexible flat feet (mean age = 23.2 ± 3 years) for three different foot orthosis conditions: soft, semi-rigid and rigid University of California Biomechanics Laboratory (UCBL). Maximum midfoot width at 90% with arch mobility in the coronal plane was shown in the semi-rigid orthosis condition. The semi-rigid orthosis resulted in the highest mean foot mobility in 90% of weight bearing, and the rigid orthosis (UCBL) had the lowest mean foot mobility. The soft orthosis resulted in foot mobility between that of the rigid and the semi-rigid orthosis. UCBL orthosis showed the highest arch height index, and the semi-rigid orthosis showed the lowest mean arch height index. Due to its rigid structure and long medial-lateral walls, the UCBL orthosis appears to limit foot mobility. Therefore, it is necessary to make an orthosis that facilitates foot mobility in the normal range of the foot arch. Future studies should address the dynamic mobility of the foot with using various types of foot orthoses. Although there are many studies focussed on flat foot and the use of foot orthoses, the mechanism of action is still unclear. This study explored foot mobility and the influence of foot orthoses and showed that a more rigid foot orthosis should be selected based on foot mobility. © The International Society for Prosthetics and Orthotics 2014.

Monitoring system of arch bridge for safety network management

NASA Astrophysics Data System (ADS)

Joo, Bong Chul; Yoo, Young Jun; Lee, Chin Hyung; Park, Ki Tae; Hwang, Yoon Koog

2010-03-01

Korea has constructed the safety management network monitoring test systems for the civil infrastructure since 2006 which includes airport structure, irrigation structure, railroad structure, road structure, and underground structure. Bridges among the road structure include the various superstructure types which are Steel box girder bridge, suspension bridge, PSC-box-girder bridge, and arch bridge. This paper shows the process of constructing the real-time monitoring system for the arch bridge and the measured result by the system. The arch type among various superstructure types has not only the structural efficiency but the visual beauty, because the arch type superstructure makes full use of the feature of curve. The main measuring points of arch bridges composited by curved members make a difference to compare with the system of girder bridges composited by straight members. This paper also shows the method to construct the monitoring system that considers the characteristic of the arch bridge. The system now includes strain gauges and thermometers, and it will include various sensor types such as CCTV, accelerometers and so on additionally. For the long term and accuracy monitoring, the latest optical sensors and equipments are applied to the system.

Thin-plate spline analysis of arch form in a Southern European population with an ideal natural occlusion.

PubMed

Camporesi, Matteo; Franchi, Lorenzo; Baccetti, Tiziano; Antonini, Antonino

2006-04-01

The purpose of the present study was to identify the mean configuration of the clinical arch form in a sample of Southern European subjects with ideal natural occlusion by means of Procrustes analysis, and to compare the identified configuration with 10 commercially produced arch forms by means of thin-plate spline (TPS) analysis. The sample comprised the study casts of 50 subjects (26 males and 24 females). The mean age of the sample was 26 years +/- 4 years. All subjects were young Caucasian adults of Southern European ancestry, and presented with an ideal natural occlusion. The three-dimensional (3D) co-ordinates of all dental points (facial axis points) were digitized using a 3D electromagnetic digitizer. The morphometric technique of TPS analysis with permutation tests was used to compare the configurations of landmarks in the various specimens. No sexual dimorphism was found for either upper or lower arch forms when the shape of the arches was assessed independently from size. The commercially available arch form that showed the least, though statistically significant, shape difference with respect to the average calculated configuration was the Brader arch form.

Three-dimensional dental arch changes of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusion.

PubMed

Peixoto, Adriano Porto; dos Santos Pinto, Ary; Garib, Daniela Gamba; Gonçalves, João Roberto

2014-01-01

This study assessed the three-dimensional changes in the dental arch of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusions at three different periods. Landmarks previously identified on upper and lower dental casts were digitized on a three-dimensional digitizer MicroScribe-3DX and stored in Excel worksheets in order to assess the width, length and depth of patient's dental arches. During orthodontic preparation, the maxillary and mandibular transverse dimensions measured at the premolar regions were increased and maintained throughout the follow-up period. Intercanine width was increased only in the upper arch during orthodontic preparation. Maxillary arch length was reduced during orthodontic finalization, only. Upper and lower arch depths were stable in the study periods. Differences between changes in centroid and gingival points suggested that upper and lower premolars buccaly proclined during the pre-surgical period. Maxillary and mandibular dental arches presented transverse expansion at premolar regions during preoperative orthodontic preparation, with a tendency towards buccal tipping. The transverse dimensions were not altered after surgery. No sagittal or vertical changes were observed during the follow-up periods.

Percutaneous Pediculoplasty for Vertebral Hemangioma Involving the Neural Arch: A Case Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuwa, Sokun, E-mail: sofuwa@luke.or.jp; Numaguchi, Yuji; Kobayashi, Nobuo

2008-01-15

Vertebral hemangiomas occasionally involve the neural arch and they can be symptomatic. We report a case of symptomatic vertebral hemangioma mainly involving the unilateral neural arch which was successfully treated with percutaneous pediculoplasty using a single-needle technique.

ELEVATION VIEW OF THE REX T. BARBER BRIDGE ARCH CONSTRUCTION, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ELEVATION VIEW OF THE REX T. BARBER BRIDGE ARCH CONSTRUCTION, VIEW OF NORTH ARCH FOLLOWING REMOVAL OF TRAVELING FORMWORK, VIEW TO EAST. - Rex T. Barber Veterans Memorial Bridge, Spanning Crooked River Gorge, Dalles-California Highway (US 97), Terrebonne, Deschutes County, OR

PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE ARCH CONSTRUCTION, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE ARCH CONSTRUCTION, VIEW OF SOUTH TRAVELING FORMWORK AND NORTH ARCH PRIOR TO CLOSURE POUR. - Rex T. Barber Veterans Memorial Bridge, Spanning Crooked River Gorge, Dalles-California Highway (US 97), Terrebonne, Deschutes County, OR

Cardiac surgery or interventional cardiology? Why not both? Let's go hybrid.

PubMed

Papakonstantinou, Nikolaos A; Baikoussis, Nikolaos G; Dedeilias, Panagiotis; Argiriou, Michalis; Charitos, Christos

2017-01-01

A hybrid strategy, firstly performed in the 1990s, is a combination of tools available only in the catheterization laboratory with those available only in the operating room in order to minimize surgical morbidity and face with any cardiovascular lesion. The continuous evolution of stent technology along with the adoption of minimally invasive surgical approaches, make hybrid approaches an attractive alternative to standard surgical or transcatheter techniques for any given set of cardiovascular lesions. Examples include hybrid coronary revascularization, when an open surgical anastomosis of the left internal mammary artery to the left anterior descending coronary artery is performed along with stent implantation in non-left anterior descending coronary vessels, open heart valve surgery combined with percutaneous coronary interventions to coronary lesions, hybrid aortic arch debranching combined with endovascular grafting for thoracic aortic aneurysms, hybrid endocardial and epicardial atrial fibrillation procedures, and carotid artery stenting along with coronary artery bypass grafting. The cornerstone of success for all of these methods is the productive collaboration between cardiac surgeons and interventional cardiologists. The indications and patient selection of these procedures are still to be defined. However, high-risk patients have already been shown to benefit from hybrid approaches. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

First Branchial Arch Fistula: A Rarity and a Surgical Challenge.

PubMed

Rajkumar, J S; Ganesh, Deepa; Anirudh, J R; Akbar, S; Joshi, Niraj

2016-06-01

Although 2(nd) Branchial arch fistulae (from incomplete closure of Cervical sinus of His) are well known, 1(st) arch fistulae are much rarer (<10%) and are usually not tackled comprehensively. We present a case of a rare first branchial arch fistula of the type II Arnot classification, which presented with two external openings of more than 20 years duration. Patient had a successful resection of all the concerned fistulous tract. Review of literature and the surgical challenges of the procedure are presented herewith.

13. Photocopy of a photographca. 1896showing wooden arch bridge over ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Photocopy of a photograph--ca. 1896--showing wooden arch bridge over the North Fork of the San Joaquin River northeast of Fresno, CA. This structure was designed by Eastwood as part of the San Joaquin Electric Company's hydro-electric plant; it is a design that indicates his interest in the structural capabilities of the arch before he began building multiple arch dams. Courtesy Mr. Charles Allan Whitney. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

Variations in tooth size and arch dimensions in Malay schoolchildren.

PubMed

Hussein, Khalid W; Rajion, Zainul A; Hassan, Rozita; Noor, Siti Noor Fazliah Mohd

2009-11-01

To compare the mesio-distal tooth sizes and dental arch dimensions in Malay boys and girls with Class I, Class II and Class III malocclusions. The dental casts of 150 subjects (78 boys, 72 girls), between 12 and 16 years of age, with Class I, Class II and Class III malocclusions were used. Each group consisted of 50 subjects. An electronic digital caliper was used to measure the mesio-distal tooth sizes of the upper and lower permanent teeth (first molar to first molar), the intercanine and intermolar widths. The arch lengths and arch perimeters were measured with AutoCAD software (Autodesk Inc., San Rafael, CA, U.S.A.). The mesio-distal dimensions of the upper lateral incisors and canines in the Class I malocclusion group were significantly smaller than the corresponding teeth in the Class III and Class II groups, respectively. The lower canines and first molars were significantly smaller in the Class I group than the corresponding teeth in the Class II group. The lower intercanine width was significantly smaller in the Class II group as compared with the Class I group, and the upper intermolar width was significantly larger in Class III group as compared with the Class II group. There were no significant differences in the arch perimeters or arch lengths. The boys had significantly wider teeth than the girls, except for the left lower second premolar. The boys also had larger upper and lower intermolar widths and lower intercanine width than the girls. Small, but statistically significant, differences in tooth sizes are not necessarily accompanied by significant arch width, arch length or arch perimeter differences. Generally, boys have wider teeth, larger lower intercanine width and upper and lower intermolar widths than girls.

Elastic energy within the human plantar aponeurosis contributes to arch shortening during the push-off phase of running.

PubMed

Wager, Justin C; Challis, John H

2016-03-21

During locomotion, the lower limb tendons undergo stretch and recoil, functioning like springs that recycle energy with each step. Cadaveric testing has demonstrated that the arch of the foot operates in this capacity during simple loading, yet it remains unclear whether this function exists during locomotion. In this study, one of the arch׳s passive elastic tissues (the plantar aponeurosis; PA) was investigated to glean insights about it and the entire arch of the foot during running. Subject specific computer models of the foot were driven using the kinematics of eight subjects running at 3.1m/s using two initial contact patterns (rearfoot and non-rearfoot). These models were used to estimate PA strain, force, and elastic energy storage during the stance phase. To examine the release of stored energy, the foot joint moments, powers, and work created by the PA were computed. Mean elastic energy stored in the PA was 3.1±1.6J, which was comparable to in situ testing values. Changes to the initial contact pattern did not change elastic energy storage or late stance PA function, but did alter PA pre-tensioning and function during early stance. In both initial contact patterns conditions, the PA power was positive during late stance, which reveals that the release of the stored elastic energy assists with shortening of the arch during push-off. As the PA is just one of the arch׳s passive elastic tissues, the entire arch may store additional energy and impact the metabolic cost of running. Copyright © 2016 Elsevier Ltd. All rights reserved.

A study of the response of nonlinear springs

NASA Technical Reports Server (NTRS)

Hyer, M. W.; Knott, T. W.; Johnson, E. R.

1991-01-01

The various phases to developing a methodology for studying the response of a spring-reinforced arch subjected to a point load are discussed. The arch is simply supported at its ends with both the spring and the point load assumed to be at midspan. The spring is present to off-set the typical snap through behavior normally associated with arches, and to provide a structure that responds with constant resistance over a finite displacement. The various phases discussed consist of the following: (1) development of the closed-form solution for the shallow arch case; (2) development of a finite difference analysis to study (shallow) arches; and (3) development of a finite element analysis for studying more general shallow and nonshallow arches. The two numerical analyses rely on a continuation scheme to move the solution past limit points, and to move onto bifurcated paths, both characteristics being common to the arch problem. An eigenvalue method is used for a continuation scheme. The finite difference analysis is based on a mixed formulation (force and displacement variables) of the governing equations. The governing equations for the mixed formulation are in first order form, making the finite difference implementation convenient. However, the mixed formulation is not well-suited for the eigenvalue continuation scheme. This provided the motivation for the displacement based finite element analysis. Both the finite difference and the finite element analyses are compared with the closed form shallow arch solution. Agreement is excellent, except for the potential problems with the finite difference analysis and the continuation scheme. Agreement between the finite element analysis and another investigator's numerical analysis for deep arches is also good.

Evaluation of arch width variations among different skeletal patterns in South Indian population

PubMed Central

Prasad, Mandava; Kannampallil, Senny Thomas; Talapaneni, Ashok Kumar; George, Suja Ani; Shetty, Sharath Kumar

2013-01-01

Background: Anterior cranial base can be taken as a reference line (SN) to determine the steepness of mandibular plane. Subjects with high mandibular plane angle tend to have a long face and one with low MP-SN angle has a shorter face. Objective: This study was done to investigate if dental arch widths correlated with vertical facial types and if there are any differences in arch widths between untreated male and female adults in South Indian population. Materials and Methods: Lateral cephalogram and dental casts were obtained from 180 untreated South Indian adults (90 males and 90 females) above 18 year old with no cross bite, minimal crowding and spacing. The angle between the anterior cranial base and the mandibular plane was measured on lateral cephalogram of each patient. Dental casts were used to obtain comprehensive dental measurements including maxillary and mandibular inter canine, inter premolar and inter molar widths, as well as amount of crowding or spacing. Results: The results showed that male arch widths were significantly larger than those of females (P < 0.05) and there was a significant decrease in inter arch width as the MP-SN angle increased in untreated adult South Indian population. The results obtained in our study when compared with studies done in other population groups showed that there is difference in inter arch widths according to ethnicity and race. Conclusion: It was concluded that the dental arch width is associated with gender, race and vertical facial morphology. Thus using individualized arch wires according to each patient's pre treatment arch form and width is suggested during orthodontic treatment. PMID:23633842

The Relationships between Foot Arch Volumes and Dynamic Plantar Pressure during Midstance of Walking in Preschool Children

PubMed Central

Chang, Hsun-Wen; Chieh, Hsiao-Feng; Lin, Chien-Ju; Su, Fong-Chin; Tsai, Ming-June

2014-01-01

Objectives The purpose of this study was to examine the correlation between the foot arch volume measured from static positions and the plantar pressure distribution during walking. Methods A total of 27 children, two to six years of age, were included in this study. Measurements of static foot posture were obtained, including navicular height and foot arch volume in sitting and standing positions. Plantar pressure, force and contact areas under ten different regions of the foot were obtained during walking. Results The foot arch index was correlated (r = 0.32) with the pressure difference under the midfoot during the foot flat phase. The navicular heights and foot arch volumes in sitting and standing positions were correlated with the mean forces and pressures under the first (r = −0.296∼−0.355) and second metatarsals (r = −0.335∼−0.504) and midfoot (r = −0.331∼−0.496) during the stance phase of walking. The contact areas under the foot were correlated with the foot arch parameters, except for the area under the midfoot. Conclusions The foot arch index measured in a static position could be a functional index to predict the dynamic foot functions when walking. The foot arch is a factor which will influence the pressure distribution under the foot. Children with a lower foot arch demonstrated higher mean pressure and force under the medial forefoot and midfoot, and lower contact areas under the foot, except for the midfoot region. Therefore, children with flatfoot may shift their body weight to a more medial foot position when walking, and could be at a higher risk of soft tissue injury in this area. PMID:24736650

Origin of the Blytheville Arch, and long-term displacement on the New Madrid seismic zone, central United States

USGS Publications Warehouse

Pratt, Thomas L.; Williams, Robert; Odum, Jackson K.; Stephenson, William J.

2013-01-01

The southern arm of the New Madrid seismic zone of the central United States coincides with the buried, ~110 km by ~20 km Blytheville Arch antiform within the Cambrian–Ordovician Reelfoot rift graben. The Blytheville Arch has been interpreted at various times as a compressive structure, an igneous intrusion, or a sediment diapir. Reprocessed industry seismic-reflection profiles presented here show a strong similarity between the Blytheville Arch and pop-up structures, or flower structures, within strike-slip fault systems. The Blytheville Arch formed in the Paleozoic, but post–Mid-Cretaceous to Quaternary strata show displacement or folding indicative of faulting. Faults within the graben structure but outside of the Blytheville Arch also appear to displace Upper Cretaceous and perhaps younger strata, indicating that past faulting was not restricted to the Blytheville Arch and New Madrid seismic zone. As much as 10–12.5 km of strike slip can be estimated from apparent shearing of the Reelfoot arm of the New Madrid seismic zone. There also appears to be ~5–5.5 km of shearing of the Reelfoot topographic scarp at the north end of the southern arm of the New Madrid seismic zone and of the southern portion of Crowley's Ridge, which is a north-trending topographic ridge just south of the seismic zone. These observations suggest that there has been substantial strike-slip displacement along the Blytheville Arch and southern arm of the New Madrid seismic zone, that strike-slip extended north and south of the modern seismic zone, and that post–Mid-Cretaceous (post-Eocene?) faulting was not restricted to the Blytheville Arch or to currently active faults within the New Madrid seismic zone.

Evaluation of robotic endovascular catheters for arch vessel cannulation.

PubMed

Riga, Celia V; Bicknell, Colin D; Hamady, Mohamad S; Cheshire, Nicholas J W

2011-09-01

Conventional catheter instability and embolization risk limits the adoption of endovascular therapy in patients with challenging arch anatomy. This study investigated whether arch vessel cannulation can be enhanced by a remotely steerable robotic catheter system. Seventeen clinicians with varying endovascular experience cannulated all arch vessels within two computed tomography-reconstructed pulsatile flow phantoms (bovine type I and type III aortic arches), under fluoroscopic guidance, using conventional and robotic techniques. Quantitative (catheterization times, catheter tip movements, vessel wall hits, catheter deflection) and qualitative metrics (Imperial College Complex Endovascular Cannulation Scoring Tool [IC3ST]) performance scores were compared. Robotic catheterization techniques resulted in a significant reduction in median carotid artery cannulation times and the median number of catheter tip movements for all vessels. Vessel wall contact with the aortic arch wall was reduced to a median of zero with robotic catheters. During stiff guidewire exchanges, robotic catheters maintained stability with zero deflection, independent of the distance the catheter was introduced into the carotid vessels. Overall IC3ST performance scores (interquartile range) were significantly improved using the robotic system: Type I arch score was 26/35 (20-30.8) vs 33/35 (31-34; P = .001), and type III arch score was 20.5/35 (16.5-28.5) vs 26.5/35 (23.5-28.8; P = .001). Low- and medium-volume interventionalists demonstrated an improvement in performance with robotic cannulation techniques. The high-volume intervention group did not show statistically significant improvement, but cannulation times, movements, and vessel wall hits were significantly reduced. Robotic technology has the potential to reduce the time, risk of embolization and catheter dislodgement, radiation exposure, and the manual skill required for carotid and arch vessel cannulation, while improving overall performance scores. Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Safety and efficacy of retrograde cerebral perfusion as an adjunct for cerebral protection during surgery on the aortic arch.

PubMed

Girardi, Leonard N; Shavladze, Nikolay; Sedrakyan, Art; Neragi-Miandoab, Siyamek

2014-12-01

The best adjunct for cerebral protection during aortic arch reconstruction remains controversial. Retrograde cerebral perfusion (RCP) as an adjunct to profound hypothermic circulatory arrest (PHCA) extends the tolerable period of brain ischemia by flushing emboli and air from the cerebral circulation while maintaining hypothermia. We examined our experience with RCP to determine its efficacy in patients undergoing complex arch reconstruction. We retrospectively evaluated 879 patients undergoing arch reconstruction using RCP from July 1997 to March 2013. Perioperative risk factors were analyzed as predictors of neurologic injury and mortality. Survival for the type of arch reconstruction and for the interval of PHCA was calculated. Of the 879 patients, 671 underwent hemiarch and 208 total arch replacement. The mean age was 65 ± 13.3 years, and 61.6% were men. The total arch patients had longer mean periods of PHCA (39 vs 21 minutes, P < .001) and RCP (37 vs 19 minutes, P < .001). However, the incidence of transient neurologic dysfunction (3.0% vs 2.4%, P < .813) and permanent neurologic dysfunction (1.3% vs 1.9%, P < .519) was similar for both techniques. Mortality was greater in the hemiarch group (4.8% vs 0.5%, P < .003). Patients requiring >40 minutes of PHCA had outcomes similar to those requiring less. The 1-, 5-, and 10-year survival was similar, regardless of the procedure performed or interval of PHCA. RCP is a safe and effective adjunct for cerebral protection during arch surgery. Patients requiring more extensive arch reconstruction are not at greater risk of permanent neurologic dysfunction or perioperative mortality. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Siphon flows in isolated magnetic flux tubes. 3: The equilibrium path of the flux tube arch

NASA Technical Reports Server (NTRS)

Thomas, John H.; Montesinis, Benjamin

1989-01-01

The arched equilibrium path of a thin magnetic flux tube in a plane-stratified, nonmagnetic atmosphere is calculated for cases in which the flux tube contains a steady siphon flow. The large scale mechanical equilibrium of the flux tube involves a balance among the magnetic buoyancy force, the net magnetic tension force due to the curvature of the flux tube axis, and the inertial (centrifugal) force due to the siphon flow along curved streamlines. The ends of the flux tube are assumed to be pinned down by some other external force. Both isothermal and adiabatic siphon flows are considered for flux tubes in an isothermal external atmosphere. For the isothermal case, in the absence of a siphon flow the equilibrium path reduces to the static arch calculated by Parker (1975, 1979). The presence of a siphon flow causes the flux tube arch to bend more sharply, so that magnetic tension can overcome the additional straightening effect of the inertial force, and reduces the maximum width of the arch. The curvature of the arch increases as the siphon flow speed increases. For a critical siphon flow, with supercritical flow in the downstream leg, the arch is asymmetric, with greater curvature in the downstream leg of the arch. Adiabatic flow have qualitatively similar effects, except that adiabatic cooling reduces the buoyancy of the flux tube and thus leads to significantly wider arches. In some cases the cooling is strong enough to create negative buoyancy along sections of the flux tube, requiring upward curvature of the flux tube path along these sections and sometimes leading to unusual equilibrium paths of periodic, sinusoidal form.

Clinical comparison and performance perspective of three aligning arch wires.

PubMed

Evans, T J; Jones, M L; Newcombe, R G

1998-07-01

To clinically evaluate three commonly used orthodontic tooth aligning arch wires: 016 x 022 inch active martensitic medium force nickel titanium, 016 x 022 inch graded force active martensitic nickel titanium, and 0.0155 inch multistrand stainless steel. A prospective randomized clinical trial. Measured serial study casts of dental arches for 112 assigned arch wires from 56 consecutive patients. Analysis based on completed records for 98 arch wires and 51 patients. A consecutive sample of 56 patients requiring both upper and lower fixed appliance therapy were randomly allocated two different arch wires from a possible three under trial. Good quality impressions were taken of the dental arches at the designated serial stages of alignment (start, T0; 4 weeks, T4; 8 weeks, T8). The resultant casts were measured on a Reflex Microscope to record the change in individual tooth alignment both in three and two dimensions (horizontal plane only). The measurement error was within acceptable limits (range, 0.05 to 0.09 mm) and showed no significant bias. ANOVA statistical models were fitted to the data to adjust for a number of variables. No significant difference in aligning capability (p > 0.05), in either two or three dimensions, was demonstrated between the three arch wires in the trial. Heat activated nickel titanium arch wires failed to demonstrate a better performance than the cheaper multistrand stainless steel wires in this randomized clinical trial. The failure to demonstrate in vivo superiority at the clinical level may be due to the confounding effects of large variations in individual metabolic response. Alternatively, it may be that in routine clinical practice NiTi-type wires are not sufficiently deformed to allow their full superelastic properties to come in to play during initial alignment.

Servicing a globally broadcast interrupt signal in a multi-threaded computer

DOEpatents

Attinella, John E.; Davis, Kristan D.; Musselman, Roy G.; Satterfield, David L.

2015-12-29

Methods, apparatuses, and computer program products for servicing a globally broadcast interrupt signal in a multi-threaded computer comprising a plurality of processor threads. Embodiments include an interrupt controller indicating in a plurality of local interrupt status locations that a globally broadcast interrupt signal has been received by the interrupt controller. Embodiments also include a thread determining that a local interrupt status location corresponding to the thread indicates that the globally broadcast interrupt signal has been received by the interrupt controller. Embodiments also include the thread processing one or more entries in a global interrupt status bit queue based on whether global interrupt status bits associated with the globally broadcast interrupt signal are locked. Each entry in the global interrupt status bit queue corresponds to a queued global interrupt.

Cardiovascular cine imaging and flow evaluation using Fast Interrupted Steady-State (FISS) magnetic resonance.

PubMed

Edelman, Robert R; Serhal, Ali; Pursnani, Amit; Pang, Jianing; Koktzoglou, Ioannis

2018-02-19

Existing cine imaging techniques rely on balanced steady-state free precession (bSSFP) or spoiled gradient-echo readouts, each of which has limitations. For instance, with bSSFP, artifacts occur from rapid through-plane flow and off-resonance effects. We hypothesized that a prototype cine technique, radial fast interrupted steady-state (FISS), could overcome these limitations. The technique was compared with standard cine bSSFP for cardiac function, coronary artery conspicuity, and aortic valve morphology. Given its advantageous properties, we further hypothesized that the cine FISS technique, in combination with arterial spin labeling (ASL), could provide an alternative to phase contrast for visualizing in-plane flow patterns within the aorta and branch vessels. The study was IRB-approved and subjects provided consent. Breath-hold cine FISS and bSSFP were acquired using similar imaging parameters. There was no significant difference in biplane left ventricular ejection fraction or cardiac image quality between the two techniques. Compared with cine bSSFP, cine FISS demonstrated a marked decrease in fat signal which improved conspicuity of the coronary arteries, while suppression of through-plane flow artifact on thin-slice cine FISS images improved visualization of the aortic valve. Banding artifacts in the subcutaneous tissues were reduced. In healthy subjects, dynamic flow patterns were well visualized in the aorta, coronary and renal arteries using cine FISS ASL, even when the slice was substantially thicker than the vessel diameter. Cine FISS demonstrates several benefits for cardiovascular imaging compared with cine bSSFP, including better suppression of fat signal and reduced artifacts from through-plane flow and off-resonance effects. The main drawback is a slight (~ 20%) decrease in temporal resolution. In addition, preliminary results suggest that cine FISS ASL provides a potential alternative to phase contrast techniques for in-plane flow quantification, while enabling an efficient, visually-appealing, semi-projective display of blood flow patterns throughout the course of an artery and its branches.

Transforce lingual appliances pre-adjusted invisible appliances simplify treatment.

PubMed

Clark, William John

2011-01-01

Transforce lingual appliances are designed to be used in conjunction with conventional fixed appliances. Lingual arch development is normally followed by bonded fixed appliances to detail the occlusion. Alternatively Transforce appliance treatment is an efficient method of preparing complex malocclusions prior to a finishing stage with invisible appliances. This approach is ideal for adult treatment, using light continuous forces for arch development with appliances that are comfortable to wear. Sagittal and Transverse appliances are designed for arch development in a range of sizes for contracted arches. They can be used to treat all classes of malocclusion and are pre-adjusted fixed/removable devices for non-compliance treatment. Force modules with nickel titanium coil springs enclosed in a tube deliver a gentle, biocompatible continuous force with a long range of action. They are excellent for mixed dentition and ideal for adult arch development. There are multiple sizes for upper and lower arch development and a sizing chart may be placed over a study model for correct selection, eliminating the need for laboratory work.

Siphon flows in isolated magnetic flux tubes. III - The equilibrium path of the flux-tube arch

NASA Technical Reports Server (NTRS)

Thomas, John H.; Montesinos, Benjamin

1990-01-01

It is shown how to calculate the equilibrium path of a thin magnetic flux tube in a stratified, nonmagnetic atmosphere when the flux tube contains a steady siphon flow. The equilbrium path of a static thin flux tube in an infinite stratified atmosphere generally takes the form of a symmetric arch of finite width, with the flux tube becoming vertical at either end of the arch. A siphon flow within the flux tube increases the curvature of the arched equilibrium path in order that the net magnetic tension force can balance the inertial force of the flow, which tries to straighten the flux tube. Thus, a siphon flow reduces the width of the arched equilibrium path, with faster flows producing narrower arches. The effect of the siphon flow on the equilibrium path is generally greater for flux tubes of weaker magnetic field strength. Examples of the equilibrium are shown for both isothemal and adiabatic siphon flows in thin flux tubes in an isothermal external atmosphere.

The hypothenar radial arch, a genetically determined epidermal ridge configuration.

PubMed

Holt, S B

1975-03-01

A radial arch in the hypothenar area of the human palm is an uncommon ridge arrangement. It is associated with an ulnar triradius and no axial triradius is present. The configuration generally occurs on right hands but is sometimes found on both hands. The frequency in the few European populations studied and in one Canadian sample varies from 0.2 per cent to over 2 per cent of persons. Hypothenar radial arches have also been reported in patients with abnormal sex chromosomes but are not specific to any karyotype. Two families are described in which nearly related persons have hypothenar radial arches. They provide the first evidence that the pattern is inherited. In one family three out of six sibs have radial arches in the hypothenar area and so have two out of three children of one of them. In the other family a pair of identical twins and their mother have hypothenar radial arches. It is suggested that, from the information available, inheritance is probably due to a recessive gene.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Attinella, John E.; Davis, Kristan D.; Musselman, Roy G.

Methods, apparatuses, and computer program products for servicing a globally broadcast interrupt signal in a multi-threaded computer comprising a plurality of processor threads. Embodiments include an interrupt controller indicating in a plurality of local interrupt status locations that a globally broadcast interrupt signal has been received by the interrupt controller. Embodiments also include a thread determining that a local interrupt status location corresponding to the thread indicates that the globally broadcast interrupt signal has been received by the interrupt controller. Embodiments also include the thread processing one or more entries in a global interrupt status bit queue based on whethermore » global interrupt status bits associated with the globally broadcast interrupt signal are locked. Each entry in the global interrupt status bit queue corresponds to a queued global interrupt.« less

A quantitative method for defining high-arched palate using the Tcof1(+/-) mutant mouse as a model.

PubMed

Conley, Zachary R; Hague, Molly; Kurosaka, Hiroshi; Dixon, Jill; Dixon, Michael J; Trainor, Paul A

2016-07-15

The palate functions as the roof of the mouth in mammals, separating the oral and nasal cavities. Its complex embryonic development and assembly poses unique susceptibilities to intrinsic and extrinsic disruptions. Such disruptions may cause failure of the developing palatal shelves to fuse along the midline resulting in a cleft. In other cases the palate may fuse at an arch, resulting in a vaulted oral cavity, termed high-arched palate. There are many models available for studying the pathogenesis of cleft palate but a relative paucity for high-arched palate. One condition exhibiting either cleft palate or high-arched palate is Treacher Collins syndrome, a congenital disorder characterized by numerous craniofacial anomalies. We quantitatively analyzed palatal perturbations in the Tcof1(+/-) mouse model of Treacher Collins syndrome, which phenocopies the condition in humans. We discovered that 46% of Tcof1(+/-) mutant embryos and new born pups exhibit either soft clefts or full clefts. In addition, 17% of Tcof1(+/-) mutants were found to exhibit high-arched palate, defined as two sigma above the corresponding wild-type population mean for height and angular based arch measurements. Furthermore, palatal shelf length and shelf width were decreased in all Tcof1(+/-) mutant embryos and pups compared to controls. Interestingly, these phenotypes were subsequently ameliorated through genetic inhibition of p53. The results of our study therefore provide a simple, reproducible and quantitative method for investigating models of high-arched palate. Copyright © 2015 Elsevier Inc. All rights reserved.

A quantitative method for defining high-arched palate using the Tcof1+/− mutant mouse as a model

PubMed Central

Conley, Zachary R.; Hague, Molly; Kurosaka, Hiroshi; Dixon, Jill; Dixon, Michael J.; Trainor, Paul A.

2016-01-01

The palate functions as the roof of the mouth in mammals, separating the oral and nasal cavities. Its complex embryonic development and assembly poses unique susceptibilities to intrinsic and extrinsic disruptions. Such disruptions may cause failure of the developing palatal shelves to fuse along the midline resulting in a cleft. In other cases the palate may fuse at an arch, resulting in a vaulted oral cavity, termed high-arched palate. There are many models available for studying the pathogenesis of cleft palate but a relative paucity for high-arched palate. One condition exhibiting either cleft palate or high-arched palate is Treacher Collins syndrome, a congenital disorder characterized by numerous craniofacial anomalies. We quantitatively analyzed palatal perturbations in the Tcof1+/− mouse model of Treacher Collins syndrome, which phenocopies the condition in humans. We discovered that 46% of Tcof1+/− mutant embryos and new born pups exhibit either soft clefts or full clefts. In addition, 17% of Tcof1+/− mutants were found to exhibit high-arched palate, defined as two sigma above the corresponding wild-type population mean for height and angular based arch measurements. Furthermore, palatal shelf length and shelf width were decreased in all Tcof1+/− mutant embryos and pups compared to controls. Interestingly, these phenotypes were subsequently ameliorated through genetic inhibition of p53. The results of our study therefore provide a simple, reproducible and quantitative method for investigating models of high-arched palate. PMID:26772999

Aqua splint suture technique in isolated zygomatic arch fractures.

PubMed

Kim, Dong-Kyu; Kim, Seung Kyun; Lee, Jun Ho; Park, Chan Hum

2014-04-01

Various methods have been used to treat zygomatic arch fractures, but no optimal modality exists for reducing these fractures and supporting the depressed bone fragments without causing esthetic problems and discomfort for life. We developed a novel aqua splint and suture technique for stabilizing isolated zygomatic arch fractures. The objective of this study is to evaluate the effect of novel aqua splint and suture technique in isolated zygomatic arch fractures. Patients with isolated zygomatic arch fractures were treated by a single surgeon in a single center from January 2000 through December 2012. Classic Gillies approach without external fixation was performed from January 2000 to December 2003, while the novel technique has been performed since 2004. 67 consecutive patients were included (Classic method, n = 32 and Novel method, n = 35). An informed consent was obtained from all patients. The novel aqua splint and suture technique was performed by the following fashion: first, we evaluated intraoperatively the bony alignment by ultrasonography and then, reduced the depressed fracture surgically using the Gillies approach. Thereafter, to stabilize the fracture and obtain the smooth facial figure, we made an aqua splint that fit the facial contour and placed monofilament nonabsorbable sutures around the fractured zygomatic arch. The novel aqua splint and suture technique showed significantly correlated with better cosmetic and functional results. In conclusion, the aqua splint suture technique is very simple, quick, safe, and effective for stabilizing repositioned zygomatic arch fractures. The aqua splint suture technique can be a good alternative procedure in isolated zygomatic arch fractures.

How Arch Support Insoles Help Persons with Flatfoot on Uphill and Downhill Walking.

PubMed

Huang, Yu-Ping; Kim, Kwantae; Song, Chen-Yi; Chen, Yat-Hon; Peng, Hsien-Te

2017-01-01

The main purpose of this study was to investigate the effect of arch support insoles on uphill and downhill walking of persons with flatfoot. Sixteen healthy college students with flatfoot were recruited in this study. Their heart rate, peak oxygen uptake (VO 2 ), and median frequency (MDF) of surface electromyogram were recorded and analyzed. Nonparametric Wilcoxon signed-rank test was used for statistical analysis. The main results were as follows: (a) peak VO 2 significantly decreased with arch support insoles compared with flat insoles during uphill and downhill walking (arch support insole versus flat insole: uphill walking, 20.7 ± 3.6 versus 31.6 ± 5.5; downhill walking, 10.9 ± 2.3 versus 16.9 ± 4.2); (b) arch support insoles could reduce the fatigue of the rectus femoris muscle during downhill walking (MDF slope of arch support insole: 0.03 ± 1.17, flat insole: -6.56 ± 23.07); (c) insole hardness would increase not only the physical sensory input but also the fatigue of lower-limb muscles particularly for the rectus femoris muscle (MDF slope of arch support insole: -1.90 ± 1.60, flat insole: -0.83 ± 1.10) in persons with flatfoot during uphill walking. The research results show that arch support insoles could effectively be applied to persons with flatfoot to aid them during uphill and downhill walking.

Quantification of motion of the thoracic aorta after ascending aortic repair of type-A dissection.

PubMed

Suh, Ga-Young; Fleischmann, Dominik; Beygui, Ramin E; Cheng, Christopher P

2017-05-01

To quantify cardiac and respiratory deformations of the thoracic aorta after ascending aortic graft repair. Eight patients were scanned with cardiac-resolved computed tomography angiography during inspiratory/expiratory breath-holds. Aortic centerlines and lumen were extracted to compute the arclength, curvature, angulation, and cross-section shape. From systole to diastole, the angle of graft [Formula: see text] arch increased by 2.4[Formula: see text] ± 1.8[Formula: see text] (P < 0.01) and the angle of arch [Formula: see text] descending aorta decreased by 2.4[Formula: see text] ± 2.6[Formula: see text] (P < 0.05), while the effective diameter of the proximal arch decreased by 2.4 ± 1.9% (P < 0.01), a greater change than those of the graft or distal arch (P < 0.05). From inspiration to expiration, the angle of graft [Formula: see text] arch increased by 2.8[Formula: see text] ± 2.6[Formula: see text] (P < 0.02) with the peak curvature increase (P < 0.05). Shorter graft length was correlated with greater cardiac-induced graft [Formula: see text] arch angulation, and longer graft length was correlated with greater respiratory-induced arch [Formula: see text] descending aorta angulation (R [Formula: see text] 0.50). The thoracic aorta changed curvature and angulation with cardiac and respiratory influences, driven by aortic root and arch motion. The thoracic aortic geometry and deformation are correlated with the ascending aortic graft length.

Holocephalan embryos provide evidence for gill arch appendage reduction and opercular evolution in cartilaginous fishes

PubMed Central

Gillis, J. Andrew; Rawlinson, Kate A.; Bell, Justin; Lyon, Warrick S.; Baker, Clare V. H.; Shubin, Neil H.

2011-01-01

Chondrichthyans possess endoskeletal appendages called branchial rays that extend laterally from their hyoid and gill-bearing (branchial) arches. Branchial ray outgrowth, like tetrapod limb outgrowth, is maintained by Sonic hedgehog (Shh) signaling. In limbs, distal endoskeletal elements fail to form in the absence of normal Shh signaling, whereas shortened duration of Shh expression correlates with distal endoskeletal reduction in naturally variable populations. Chondrichthyans also exhibit natural variation with respect to branchial ray distribution—elasmobranchs (sharks and batoids) possess a series of ray-supported septa on their hyoid and gill arches, whereas holocephalans (chimaeras) possess a single hyoid arch ray-supported operculum. Here we show that the elongate hyoid rays of the holocephalan Callorhinchus milii grow in association with sustained Shh expression within an opercular epithelial fold, whereas Shh is only transiently expressed in the gill arches. Coincident with this transient Shh expression, branchial ray outgrowth is initiated in C. milii but is not maintained, yielding previously unrecognized vestigial gill arch branchial rays. This is in contrast to the condition seen in sharks, where sustained Shh expression corresponds to the presence of fully formed branchial rays on the hyoid and gill arches. Considered in light of current hypotheses of chondrichthyan phylogeny, our data suggest that the holocephalan operculum evolved in concert with gill arch appendage reduction by attenuation of Shh-mediated branchial ray outgrowth, and that chondrichthyan branchial rays and tetrapod limbs exhibit parallel developmental mechanisms of evolutionary reduction. PMID:21220324

Executing application function calls in response to an interrupt

DOEpatents

Almasi, Gheorghe; Archer, Charles J.; Giampapa, Mark E.; Gooding, Thomas M.; Heidelberger, Philip; Parker, Jeffrey J.

2010-05-11

Executing application function calls in response to an interrupt including creating a thread; receiving an interrupt having an interrupt type; determining whether a value of a semaphore represents that interrupts are disabled; if the value of the semaphore represents that interrupts are not disabled: calling, by the thread, one or more preconfigured functions in dependence upon the interrupt type of the interrupt; yielding the thread; and if the value of the semaphore represents that interrupts are disabled: setting the value of the semaphore to represent to a kernel that interrupts are hard-disabled; and hard-disabling interrupts at the kernel.

Initial arch wires for tooth alignment during orthodontic treatment with fixed appliances.

PubMed

Jian, Fan; Lai, Wenli; Furness, Susan; McIntyre, Grant T; Millett, Declan T; Hickman, Joy; Wang, Yan

2013-04-30

Initial arch wires are the first arch wires to be inserted into the fixed appliance at the beginning of orthodontic treatment and are used mainly for the alignment of teeth by correcting crowding and rotations. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause the least amount of root resorption and pain during the initial aligning stage of treatment. This is an update of the review 'Initial arch wires for alignment of crooked teeth with fixed orthodontic braces' first published in the Cochrane Database of Systematic Reviews 2010, Issue 4. To assess the effects of initial arch wires for alignment of teeth with fixed orthodontic braces in relation to alignment speed, root resorption and pain intensity. We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 2 August 2012), CENTRAL (The Cochrane Library 2012, Issue 7), MEDLINE via OVID (1950 to 2 August 2012) and EMBASE via OVID (1980 to 2 August 2012). We also searched the reference lists of relevant articles. There was no restriction with regard to publication status or language of publication. We contacted all authors of included studies to identify additional studies. We included randomised controlled trials (RCTs) of initial arch wires to align teeth with fixed orthodontic braces. Only studies involving participants with upper and/or lower full arch fixed orthodontic appliances were included. Two review authors were responsible for study selection, validity assessment and data extraction. All disagreements were resolved by discussion amongst the review team. Corresponding authors of included studies were contacted to obtain missing information. Nine RCTs with 571 participants were included in this review. All trials were at high risk of bias and a number of methodological limitations were identified. All trials had at least one potentially confounding factor (such as bracket type, slot size, ligation method, extraction of teeth) which is likely to have influenced the outcome and was not controlled in the trial. None of the trials reported the important adverse outcome of root resorption.Three groups of comparisons were made.(1) Multistrand stainless steel initial arch wires compared to superelastic nickel titanium (NiTi) initial arch wires. There were four trials in this group, with different comparisons and outcomes reported at different times. No meta-analysis was possible. There is insufficient evidence from these trials to determine whether or not there is a difference in either rate of alignment or pain between stainless steel and NiTi initial arch wires.(2) Conventional (stabilised) NiTi initial arch wires compared to superelastic NiTi initial arch wires. There were two trials in this group, one reporting the outcome of alignment over 6 months and the other reporting pain over 1 week. There is insufficient evidence from these trials to determine whether or not there is any difference between conventional (stabilised) and superelastic NiTi initial arch wires with regard to either alignment or pain.(3) Single-strand superelastic NiTi initial arch wires compared to other NiTi (coaxial, copper NiTi (CuNiTi) or thermoelastic) initial arch wires. The three trials in this comparison each compared a different product against single-strand superelastic NiTi. There is very weak unreliable evidence, based on one very small study (n = 24) at high risk of bias, that coaxial superelastic NiTi may produce greater tooth movement over 12 weeks, but no information on associated pain or root resorption. This result should be interpreted with caution until further research evidence is available. There is insufficient evidence to determine whether or not there is a difference between either thermoelastic or CuNiTi and superelastic NiTi initial arch wires. There is no reliable evidence from the trials included in this review that any specific initial arch wire material is better or worse than another with regard to speed of alignment or pain. There is no evidence at all about the effect of initial arch wire materials on the important adverse effect of root resorption. Further well-designed and conducted, adequately-powered, RCTs are required to determine whether the performance of initial arch wire materials as demonstrated in the laboratory, makes a clinically important difference to the alignment of teeth in the initial stage of orthodontic treatment in patients.

49 CFR 230.61 - Arch tubes, water bar tubes, circulators and thermic siphons.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Arch tubes, water bar tubes, circulators and... MAINTENANCE STANDARDS Boilers and Appurtenances Washing Boilers § 230.61 Arch tubes, water bar tubes... water bar tubes shall thoroughly be cleaned mechanically, washed, and inspected. Circulators and thermic...

4. ATTLEBORO VIADUCT SHOWING MILL STREET ARCH AT LEFT, ATTLEBORO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. ATTLEBORO VIADUCT SHOWING MILL STREET ARCH AT LEFT, ATTLEBORO STATION AT LEFT CENTER AND SOUTH MAIN STREET ARCH AT RIGHT. ATTLEBORO, BRISTOL CO., MA. Sec. 4116, MP 197.16. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

76 FR 61291 - Approval and Promulgation of Air Quality Implementation Plans; West Virginia; Ohio; Determination...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-04

.... Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103. D. Hand..., U.S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103..., Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, PA 19103-2023. The telephone number...

11. DETAIL, ARCH BARREL AND RING, FROM SOUTHWEST, SHOWING CUT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. DETAIL, ARCH BARREL AND RING, FROM SOUTHWEST, SHOWING CUT STONE MASONRY RINGSTONE VOUSSOIRS WITH '1902' KEYSTONE, CONCRETE PARAPET, CONCRETE APRON AT BASE OF BRIDGE UNDER ARCH, AND PORTION OF TIMBER GRILLAGE - Boston Street Bridge, Spanning Harris Creek Sewer at Boston Street, Baltimore, Independent City, MD

12. AN IMAGE OF THE ARCH ENTRADOS LOOKING SOUTH FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. AN IMAGE OF THE ARCH ENTRADOS LOOKING SOUTH FROM THE NORTH SIDE OF U.S. 40. THIS DETAIL CLEARLY SHOWS THE FOUR LONGITUDINAL ARCH CASTINGS AND THE GHOSTS OF THE BOARDS USED AS FORMS. - Vandalia Railroad Bridge, Spanning U.S. Route 40, Indianapolis, Marion County, IN

3. DETAIL VIEW OF ONE ARCH SPAN, LOOKING NW ALONG ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. DETAIL VIEW OF ONE ARCH SPAN, LOOKING NW ALONG EAST BANK OF SUSQUEHANNA RIVER. NOTE FLOOD STAGE MARKINGS ON PIER, ALSO LONGITUDINAL CONSTRUCTION JOINT IN ARCH BARREL. - Philadelphia & Reading Railroad, Susquehanna River Bridge, Spanning Susquehanna River, North of I-83 Bridge, Harrisburg, Dauphin County, PA

Effect of heat treatment on stainless steel lingual arch appliances.

PubMed

Nagatani, S S; Fisher, J G; Hondrum, S O

1996-01-01

This study evaluated the effect of heat treatment on 0.036" diameter stainless steel wire. Forty wires were bent into arch forms (20 experimental and 20 control). The arch width changes were measured and the forces generated were determined over an eight week period. Heat treatment resulted in immediate and significant expansion (p < 0.001) followed by stabilization of arch width. The control wires continued to expand throughout the study. The force generated by the control group and experimental group expansion was capable of producing tooth movement.

Arch-Axis Coefficient Optimization of Long-Span Deck-Type Concrete-Filled Steel Tubular Arch Bridge

NASA Astrophysics Data System (ADS)

Liu, Q. J.; Wan, S.; Liu, H. C.

2017-11-01

This paper is based on Nanpuxi super major bridge which is under construction and starts from Wencheng Zhejiang province to Taishun highway. A finite element model of the whole bridge is constructed using Midas Civil finite element software. The most adverse load combination in the specification is taken into consideration to determine the method of calculating the arch-axis coefficient of long-span deck-type concrete-filled steel tubular arch bridge. By doing this, this paper aims at providing references for similar engineering projects.

Anabolic steroid abuse and tooth size-arch dimensions in the rat.

PubMed

Barrett, R L; Harris, E F; Tolley, E A; Nutting, D F

1993-01-01

Anabolic steroids are misused by adolescents and adults to increase muscle mass and improve appearance and athletic performance. Since anabolics strongly enhance protein synthesis, it was speculated that alterations in tooth size and arch length could occur. This study quantified the effects of the anabolic steroid nandrolone phenpropionate on these parameters in a rat model. The steroid significantly increased mandibular arch length. No difference in mesiodistal dimensions of the molars occurred. In consequence, the increased arch dimensions combined with unaltered tooth size may result in dental spacing and/or other malocclusions.

Effective way to reconstruct arch bridges using concrete walls and transverse strands

NASA Astrophysics Data System (ADS)

Klusáček, Ladislav; Pěkník, Robin; Nečas, Radim

2017-09-01

There are more than 500 masonry arch bridges in the Czech Road system and about 2500 in the Czech Railway system. Many of them are cracked in the longitudinal (span) direction. The barrel vaults are separated by the cracks into partial masonry arches without load bearing connection in transverse direction. These constructions are about 150 years old and they are also too narrow for the current road system. This paper presents a strengthening method for masonry arch bridges using transverse post-tensioning. This method is very useful not only for strengthening in the transverse direction, but widening of masonry arches can be taken as secondary effect especially in case of road bridges. Several bridges were successfully repaired with the use of this system which seems to be effective and reliable.

Role of Dlx6 in regulation of an endothelin-1-dependent, dHAND branchial arch enhancer

PubMed Central

Charité, Jeroen; McFadden, David G.; Merlo, Giorgio; Levi, Giovanni; Clouthier, David E.; Yanagisawa, Masashi; Richardson, James A.; Olson, Eric N.

2001-01-01

Neural crest cells play a key role in craniofacial development. The endothelin family of secreted polypeptides regulates development of several neural crest sublineages, including the branchial arch neural crest. The basic helix–loop–helix transcription factor dHAND is also required for craniofacial development, and in endothelin-1 (ET-1) mutant embryos, dHAND expression in the branchial arches is down-regulated, implicating it as a transcriptional effector of ET-1 action. To determine the mechanism that links ET-1 signaling to dHAND transcription, we analyzed the dHAND gene for cis-regulatory elements that control transcription in the branchial arches. We describe an evolutionarily conserved dHAND enhancer that requires ET-1 signaling for activity. This enhancer contains four homeodomain binding sites that are required for branchial arch expression. By comparing protein binding to these sites in branchial arch extracts from endothelin receptor A (EdnrA) mutant and wild-type mouse embryos, we identified Dlx6, a member of the Distal-less family of homeodomain proteins, as an ET-1-dependent binding factor. Consistent with this conclusion, Dlx6 was down-regulated in branchial arches from EdnrA mutant mice. These results suggest that Dlx6 acts as an intermediary between ET-1 signaling and dHAND transcription during craniofacial morphogenesis. PMID:11711438

[Effect of dental arch length decrease during orthodontic treatment in the upper airway development. A review].

PubMed

Haddad, Stéphanie; Kerbrat, Jean-Baptiste; Schouman, Thomas; Goudot, Patrick

2017-03-01

A possible relation between an upper airway space decrease and the development of obstructive sleep apnea syndrom explains the importance to know the effect of the modification of dental arch length on the upper airway during orthodontic treatment. The aim of this article is to expose recent knowledge about upper airway development and dental arch length decrease factors, to determine the influence of this decrease on upper airway development. A review was done to determine the upper airway normal development, to define dental arch to specify if an ideal position of dental arch on apical base exists. All of the length dental arch decrease factors during orthodontic treatment (dental extraction, dental agenesis and dental malpositions) and their upper airway resounding were searched. Some authors found a diminution of upper airway space after premolars extractions while others didn't found this diminution after extractions premolars when incisor retraction is finished. A decrease of transversal maxillary diameter and nasal cavity may be due to absence of permanent teeth. The effect of dental arch length decrease during orthodontic treatment in the upper airway development was not scientifically proved. However we had to be vigilant and adapt our orthodontic treatment case by case to avoid an upper airway modification. © EDP Sciences, SFODF, 2017.

Biomechanical and clinical factors related to stage I posterior tibial tendon dysfunction.

PubMed

Rabbito, Melissa; Pohl, Michael B; Humble, Neil; Ferber, Reed

2011-10-01

Case control. To investigate differences in arch height, ankle muscle strength, and biomechanical factors in individuals with stage I posterior tibial tendon dysfunction (PTTD) in comparison to healthy individuals. PTTD is a progressive condition, so early recognition and treatment are essential to help delay or reverse the progression. However, no previous studies have investigated stage I PTTD, and no single study has measured static anatomical structure, muscle strength, and gait mechanics in this population. Twelve individuals with stage I PTTD and 12 healthy, age- and gender-matched control subjects, who were engaged in running-related activities, participated in this study. Measurements of arch height index, maximum voluntary ankle invertor muscle strength, and 3-dimensional rearfoot and medial longitudinal arch kinematics during walking were obtained. The runners with PTTD demonstrated significantly lower seated arch height index (P = .02) and greater (P = .03) and prolonged (P = .05) peak rearfoot eversion angle during gait, compared to the healthy runners. No differences were found in standing arch height index values (P = .28), arch rigidity index (P = .06), ankle invertor strength (P = .49), or peak medial longitudinal arch values (P = .49) between groups. The increased foot pronation is hypothesized to place greater strain on the posterior tibialis muscle, which may partially explain the progressive nature of this condition.

What does the transverse carpal ligament contribute to carpal stability?

PubMed

Vanhees, Matthias; Verstreken, Frederik; van Riet, Roger

2015-02-01

Background The transverse carpal ligament is well known for its involvement in carpal tunnel syndrome, and sectioning of this ligament remains the definite treatment for this pathology. Some authors believe that the transverse carpal ligament is an important stabilizer of the carpal arch, whereas others do not consider it to be significant. Several studies have been performed, both in vivo and in in vitro. Sectioning of the transverse carpal ligament does not seem to have any effect on the width of the carpal arch in the unloaded condition. However, patients will load the arch during their activities of daily living. Materials and Methods A cadaveric study was done with distraction of the carpal bones before and after sectioning the transverse carpal ligament. Results With the transverse carpal ligament intact, the carpal arch is mobile, with distraction leading up to 50% widening of the arch. Sectioning of the transverse carpal ligament resulted in a significant widening of the carpal arch by a further 30%. Conclusions Loading of the carpal arch after sectioning of the transeverse carapal ligament leads to a significant increase in intracarpal mobility. This will inevitably influence carpal kinematics in the patient and might be responsible for some complications after simple carpal tunnel releases, such as pillar pain, palmar tenderness, and loss of grip strength.

Analysis of an arched outer-race ball bearing considering centrifugal forces

NASA Technical Reports Server (NTRS)

Hamrock, B. J.; Anderson, W. J.

1972-01-01

A Newton-Raphson method of iteration was used in evaluating the radial and axial projection of the distance between the ball center and the outer raceway groove curvature center (V and W). Fatigue life evaluations were made. The similar analysis of a conventional bearing can be directly obtained from the arched bearing analysis by simply letting the amount of arching be zero (g = 0) and not considering equations related to the unloaded half of the outer race. The analysis was applied to a 150-mm angular contact ball bearing. Results for life, contact loads, and angles are shown for a conventional bearing (g = 0) and two arched bearings (g = 0.127 mm (0.005 in.), and 0.254 mm (0.010 in.)). The results indicate that an arched bearing is highly desirable for high speed applications. In particular, for a DN value of 3 million (20,000 rpm) and an applied axial load of 4448 N (1000 lb), an arched bearing shows an improvement in life of 306 percent over that of a conventional bearing. At 4.2 million DN (28,000 rpm), the corresponding improvement is 340 percent. It was also found for low speeds, the arched bearing does not offer the advantages that it does for high speed applications.

Classification and outcomes of extended arch repair for acute Type A aortic dissection: a systematic review and meta-analysis.

PubMed

Smith, Holly N; Boodhwani, Munir; Ouzounian, Maral; Saczkowski, Richard; Gregory, Alexander J; Herget, Eric J; Appoo, Jehangir J

2017-03-01

Distal extent of repair in patients undergoing surgery for acute Type A aortic dissection (ATAAD) is controversial. Emerging hybrid techniques involving open and endovascular surgery have been reported in small numbers by select individual centres. A systematic review and meta-analysis was performed to investigate the outcomes following extended arch repair for ATAAD. A classification system is proposed of the different techniques to facilitate discussion and further investigation. Using Ovid MEDLINE, 38 studies were identified reporting outcomes for 2140 patients. Studies were categorized into four groups on the basis of extent of surgical aortic resection and the method of descending thoracic aortic stent graft deployment; during circulatory arrest (frozen stented elephant trunk) or with normothermic perfusion and use of fluoroscopy (warm stent graft): (I) surgical total arch replacement, (II) total arch and frozen stented elephant trunk, (III) hemiarch and frozen stented elephant trunk and (IV) total arch and warm stent graft. Perioperative event rates were obtained for each of the four groups and the entire cohort using pooled summary estimates. Linearized rates of late mortality and reoperation were calculated. Overall pooled hospital mortality for extended arch techniques was 8.6% (95% CI 7.2-10.0). Pooled data categorized by surgical technique resulted in hospital mortality of 11.9% for total arch, 8.6% total arch and frozen stented elephant trunk, 6.3% hemiarch and frozen stented elephant trunk and 5.5% total arch and 'warm stent graft'. Overall incidence of stroke for the entire cohort was 5.7% (95% CI 3.6-8.2). Rate of spinal cord ischaemia was 2.0% (95% CI 1.2-3.0). Pooled linearized rate of late mortality was 1.66%/pt-yr (95% CI 1.34-2.07) with linearized rate of re-operation of 1.62%/pt-yr (95% CI 1.24-2.05). Perioperative results of extended arch procedures are encouraging. Further follow-up is required to see if long-term complications are reduced with these emerging techniques. The proposed classification system will facilitate future comparison of short- and long-term results of different techniques of extended arch repair for ATAAD. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

An Assessment of Curve of Spee in Healthy Human Permanent Dentitions: A Cross Sectional Analytical Study in a Group of Young Indian Population.

PubMed

Krishnamurthy, Sushma; Hallikerimath, Rajendra B; Mandroli, Praveenkumar S

2017-01-01

An awareness of the standard value of the maxillary and the mandibular curves of Spee may aid the clinician in developing occlusion in the sagittal plane and would be useful when providing prosthetic rehabilitation for patients with occlusal derangement. To assess and compare the radius and depth of curve of Spee in maxillary and mandibular arches in men and women, in a group of young Indian population. The study cohort consisted of 25 men and 25 women between 19 to 24 years. Impression of maxillary and mandibular arches were made with alginate. Casts were poured in die stone. Standardized digital pictures of the right side of maxillary and mandibular dental casts were made with a digital camera and transferred to a computer. Tips of the distal cusps of molars, premolars and canines of the maxilla and mandible were located. The radius and the depth of the curve of Spee were measured from the digital photographs of dental casts, with the help of 'dimension tool' in the computer software (Corel DRAW X5). Mann-Whitney test was used to analyze the difference in the curve of Spee between men and women and the difference between maxillary and mandibular arches. The mean values were as follows: a) Men: Radii of curve of Spee in the maxillary and mandibular arch were 140.22±65.98 and 109.67±46.80 respectively; depths of curve of Spee in maxillary and mandibular arch were 1.65±0.67 and 1.49±0.74 respectively; b) Women: Radii of curve of Spee in the maxillary and mandibular arch were 120.58±63.91 and 98.31±63.59 respectively; depths of curve of Spee in maxillary and mandibular arch were 1.45±0.54 and 1.40±0.61 respectively. In the mandibular arch, the difference in the radii (p=0.0467) was statistically significant between men and women. In women, the difference in radii (p=0.0467) between maxillary and mandibular arches was statistically significant. The radii and depths of curve of Spee were larger in maxillary than mandibular arches in both men and women. Also, the difference in the radii of mandibular arch was statistically significant between men and women.

No reliable evidence to guide initial arch wire choice for fixed appliance therapy.

PubMed

Flores-Mir, Carlos

2013-12-01

The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline and Embase databases were searched. Conference proceedings and abstracts from the British Orthodontic Conference European Orthodontic Conference and the International Association for Dental Research were also searched together with the reference lists of identified studies. Study authors were contacted for additional information. Randomised controlled trials of initial arch wire involving participants with upper and/or lower full arch fixed orthodontic appliances were included. Study selection, data extraction and risk of bias assessment were carried out independently by at least two reviewers. Nine RCTs with 571 participants were included in this review. All trials were at high risk of bias. All trials had at least one potentially confounding factor (such as bracket type, slot size, ligation method, extraction of teeth) which is likely to have influenced the outcome and was not controlled in the trial. None of the trials reported the important adverse outcome of root resorption. The comparisons were made between:Multistrand stainless steel initial arch wires compared to superelastic nickel titanium (NiTi) initial arch wires. There were four trials in this group, with different comparisons and outcomes reported at different times. No meta-analysis was possible. There is insufficient evidence from these trials to determine whether or not there is a difference in either rate of alignment or pain between stainless steel and NiTi initial arch wires.Conventional (stabilised) NiTi initial arch wires compared to superelastic NiTi initial arch wires. There were two trials in this group, one reporting the outcome of alignment over six months and the other reporting pain over one week. There is insufficient evidence from these trials to determine whether or not there is any difference between conventional (stabilised) and superelastic NiTi initial arch wires with regard to either alignment or pain.Single-strand superelastic NiTi initial arch wires compared to other NiTi (coaxial, copper NiTi (CuNiTi) or thermoelastic) initial arch wires. The three trials in this comparison each compared a different product against single-strand superelastic NiTi. There is very weak unreliable evidence, based on one very small study (n = 24) at high risk of bias, that coaxial superelastic NiTi may produce greater tooth movement over 12 weeks, but no information on associated pain or root resorption. This result should be interpreted with caution until further research evidence is available. There is insufficient evidence to determine whether or not there is a difference between either thermoelastic or CuNiTi and superelastic NiTi initial arch wires. There is no reliable evidence from the trials included in this review that any specific initial arch wire material is better or worse than another with regard to speed of alignment or pain. There is no evidence at all about the effect of initial arch wire materials on the important adverse effect of root resorption. Further well-designed and conducted, adequately-powered RCTs are required to determine whether the performance of initial arch wire materials as demonstrated in the laboratory, makes a clinically important difference to the alignment of teeth in the initial stage of orthodontic treatment in patients.

Understanding Emergency Medicine Physicians Multitasking Behaviors Around Interruptions.

PubMed

Fong, Allan; Ratwani, Raj M

2018-06-11

Interruptions can adversely impact human performance, particularly in fast-paced and high-risk environments such as the emergency department (ED). Understanding physician behaviors before, during, and after interruptions is important to the design and promotion of safe and effective workflow solutions. However, traditional human factors based interruption models do not accurately reflect the complexities of real-world environments like the ED and may not capture multiple interruptions and multitasking. We present a more comprehensive framework for understanding interruptions that is composed of three phases, each with multiple levels: Interruption Start Transition, Interruption Engagement, and Interruption End Transition. This three-phase framework is not constrained to discrete task transitions, providing a robust method to categorize multitasking behaviors around interruptions. We apply this framework in categorizing 457 interruption episodes. 457 interruption episodes were captured during 36 hours of observation. The interrupted task was immediately suspended 348 (76.1%) times. Participants engaged in new self-initiated tasks during the interrupting task 164 (35.9%) times and did not directly resume the interrupted task in 284 (62.1%) interruption episodes. Using this framework provides a more detailed description of the types of physician behaviors in complex environments. Understanding the different types of interruption and resumption patterns, which may have a different impact on performance, can support the design of interruption mitigation strategies. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

The relationship between foot arch measurements and walking parameters in children.

PubMed

Gill, Simone V; Keimig, Sara; Kelty-Stephen, Damian; Hung, Ya-Ching; DeSilva, Jeremy M

2016-01-23

Walking mechanics are influenced by body morphology. Foot arch height is one aspect of body morphology central to walking. However, generalizations about the relationship between arch height and walking are limited due to previous methodologies used for measuring the arch and the populations that have been studied. To gain the knowledge needed to support healthy gait in children and adults, we need to understand this relationship in unimpaired, typically developing children and adults using dynamic measures. The purpose of the current study was to examine the relationship between arch height and gait in a sample of healthy children and adults using dynamic measures. Data were collected from 638 participants (n = 254 children and n = 384 adults) at the Museum of Science, Boston (MOS) and from 18 4- to 8-year-olds at the Motor Development and Motor Control Laboratories. Digital footprints were used to calculate two arch indices: the Chippaux-Smirak (CSI) and the Keimig Indices (KI). The height of the navicular bone was measured. Gait parameters were captured with a mechanized gait carpet at the MOS and three-dimensional motion analyses and in-ground force plates in the Motor Development and Motor Control Laboratories. Linear regression analyses on data from the MOS confirmed that as age increases, step length increases. With a linear mixed effect regression model, we found that individuals who took longer steps had higher arches as measured by the KI. However, this relationship was no longer significant when only adults were included in the model. A model restricted to children found that amongst this sample, those with higher CSI and higher KI values take longer relative step lengths. Data from the Motor Development and Motor Control Laboratories showed that both CSI and KI added to the prediction; children with lower anterior ground reaction forces had higher CSI and higher KI values. Arch height indices were correlated with navicular height. These results suggest that more than one measure of the arch may be needed elucidate the relationship between arch height and gait.

Aortic arch shape is not associated with hypertensive response to exercise in patients with repaired congenital heart diseases.

PubMed

Ntsinjana, Hopewell N; Biglino, Giovanni; Capelli, Claudio; Tann, Oliver; Giardini, Alessandro; Derrick, Graham; Schievano, Silvia; Taylor, Andrew M

2013-11-12

Aortic arch geometry is linked to abnormal blood pressure (BP) response to maximum exercise. This study aims to quantitatively assess whether aortic arch geometry plays a role in blood pressure (BP) response to exercise. 60 age- and BSA-matched subjects--20 post-aortic coarctation (CoA) repair, 20 transposition of great arteries post arterial switch operation (ASO) and 20 healthy controls--had a three-dimensional (3D), whole heart magnetic resonance angiography (MRA) at 1.5 Tesla, 3D geometric reconstructions created from the MRA. All subjects underwent cardiopulmonary exercise test on the same day as MRA using an ergometer cycle with manual BP measurements. Geometric analysis and their correlation with BP at peak exercise were assessed. Arch curvature was similarly acute in both the post-CoA and ASO cases [0.05 ± 0.01 vs. 0.05 ± 0.01 (1/mm/m²); p = 1.0] and significantly different to that of normal healthy controls [0.05 ± 0.01 vs. 0.03 ± 0.01 (1/mm/m²), p < 0.001]. Indexed transverse arch cross sectional area were significantly abnormal in the post-CoA cases compared to the ASO cases (117.8 ± 47.7 vs. 221.3 ± 44.6; p < 0.001) and controls (117.8 ± 47.7 vs. 157.5 ± 27.2 mm²; p = 0.003). BP response to peak exercise did not correlate with arch curvature (r = 0.203, p = 0.120), but showed inverse correlation with indexed minimum cross sectional area of transverse arch and isthmus (r = -0.364, p = 0.004), and ratios of minimum arch area/ descending diameter (r = -0.491, p < 0.001). Transverse arch and isthmus hypoplasia, rather than acute arch angulation plays a role in the pathophysiology of BP response to peak exercise following CoA repair.

The effects of intrathecal midazolam on sympathetic nervous system reflexes in man--a pilot study.

PubMed Central

Goodchild, C S; Noble, J

1987-01-01

Nine patients were given intrathecal injections of midazolam (dose 0.3-2 mg dissolved in 3 ml 5% dextrose). No changes in motor power or general sensation were produced. Resting heart rate and blood pressure were unchanged and normal valsalva manoeuvres were elicited 30 min post-injection. Cardiovascular responses were provoked at a light plane of anaesthesia by intubation of the trachea and manipulation of peritoneum and bowel but not by surgical incision of the skin. Intrathecal administration of midazolam relieved post-operative pain of somatic origin but not of visceral origin. It is concluded that intrathecal midazolam in the dosage used interrupts somatic nociceptive afferent pathways but not abdominal visceral nociceptive afferent pathways. PMID:3567043

Correlation and agreement of a digital and conventional method to measure arch parameters.

PubMed

Nawi, Nes; Mohamed, Alizae Marny; Marizan Nor, Murshida; Ashar, Nor Atika

2018-01-01

The aim of the present study was to determine the overall reliability and validity of arch parameters measured digitally compared to conventional measurement. A sample of 111 plaster study models of Down syndrome (DS) patients were digitized using a blue light three-dimensional (3D) scanner. Digital and manual measurements of defined parameters were performed using Geomagic analysis software (Geomagic Studio 2014 software, 3D Systems, Rock Hill, SC, USA) on digital models and with a digital calliper (Tuten, Germany) on plaster study models. Both measurements were repeated twice to validate the intraexaminer reliability based on intraclass correlation coefficients (ICCs) using the independent t test and Pearson's correlation, respectively. The Bland-Altman method of analysis was used to evaluate the agreement of the measurement between the digital and plaster models. No statistically significant differences (p > 0.05) were found between the manual and digital methods when measuring the arch width, arch length, and space analysis. In addition, all parameters showed a significant correlation coefficient (r ≥ 0.972; p < 0.01) between all digital and manual measurements. Furthermore, a positive agreement between digital and manual measurements of the arch width (90-96%), arch length and space analysis (95-99%) were also distinguished using the Bland-Altman method. These results demonstrate that 3D blue light scanning and measurement software are able to precisely produce 3D digital model and measure arch width, arch length, and space analysis. The 3D digital model is valid to be used in various clinical applications.

Hybrid endovascular repair in aortic arch pathologies: a retrospective study.

PubMed

Ma, Xiaohui; Guo, Wei; Liu, Xiaoping; Yin, Tai; Jia, Xin; Xiong, Jiang; Zhang, Hongpeng; Wang, Lijun

2010-11-18

The aortic arch presents specific challenges to endovascular repair. Hybrid repair is increasingly evolving as an alternative option for selected patients, and promising initial results have been reported. The aim of this study was to introduce our experiences and evaluate mid-term results of supra aortic transpositions for extended endovascular repair of aortic arch pathologies. From December 2002 to January 2008, 25 patients with thoracic aortic aneurysms and dissections involving the aortic arch were treated with hybrid endovascular treatment in our center. Of the 25 cases, 14 were atherosclerotic thoracic aortic aneurysms and 11 were thoracic aortic dissection. The hybrid repair method included total-arch transpositions (15 cases) or hemi-arch transpositions (10 cases), and endovascular procedures. All hybrid endovascular procedures were completed successfully. Three early residual type-I endoleaks and one type-II endoleak were observed. Stroke occurred in three patients (8%) during the in-hospital stage. The perioperative mortality rate was 4%; one patients died post-operatively from catheter related complications. The average follow-up period was 15 ± 5.8 months (range, 1-41 months). The overall crude survival rate at 15 months was 92% (23/25). During follow-up, new late endoleaks and stent-raft related complications were not observed. One case (4%) developed a unilateral lower limb deficit at 17 days and was readmitted to hospital. In conclusion, the results are encouraging for endovascular aortic arch repair in combination with supra-aortic transposition in high risk cases. Aortic endografting offers good mid-term results. Mid-term results of the hybrid approach in elderly patients with aortic arch pathologies are satisfying.

Distinct patterns of notochord mineralization in zebrafish coincide with the localization of Osteocalcin isoform 1 during early vertebral centra formation

PubMed Central

2012-01-01

Background In chondrichthyans, basal osteichthyans and tetrapods, vertebral bodies have cartilaginous anlagen that subsequently mineralize (chondrichthyans) or ossify (osteichthyans). Chondrocytes that form the vertebral centra derive from somites. In teleost fish, vertebral centrum formation starts in the absence of cartilage, through direct mineralization of the notochord sheath. In a second step, the notochord is surrounded by somite-derived intramembranous bone. In several small teleost species, including zebrafish (Danio rerio), even haemal and neural arches form directly as intramembranous bone and only modified caudalmost arches remain cartilaginous. This study compares initial patterns of mineralization in different regions of the vertebral column in zebrafish. We ask if the absence or presence of cartilaginous arches influences the pattern of notochord sheath mineralization. Results To reveal which cells are involved in mineralization of the notochord sheath we identify proliferating cells, we trace mineralization on the histological level and we analyze cell ultrastructure by TEM. Moreover, we localize proteins and genes that are typically expressed by skeletogenic cells such as Collagen type II, Alkaline phosphatase (ALP) and Osteocalcin (Oc). Mineralization of abdominal and caudal vertebrae starts with a complete ring within the notochord sheath and prior to the formation of the bony arches. In contrast, notochord mineralization of caudal fin centra starts with a broad ventral mineral deposition, associated with the bases of the modified cartilaginous arches. Similar, arch-related, patterns of mineralization occur in teleosts that maintain cartilaginous arches throughout the spine. Throughout the entire vertebral column, we were able to co-localize ALP-positive signal with chordacentrum mineralization sites, as well as Collagen II and Oc protein accumulation in the mineralizing notochord sheath. In the caudal fin region, ALP and Oc signals were clearly produced both by the notochord epithelium and cells outside the notochord, the cartilaginous arches. Based on immunostaining, real time PCR and oc2:gfp transgenic fish, we identify Oc in the mineralizing notochord sheath as osteocalcin isoform 1 (Oc1). Conclusions If notochord mineralization occurs prior to arch formation, mineralization of the notochord sheath is ring-shaped. If notochord mineralization occurs after cartilaginous arch formation, mineralization of the notochord sheath starts at the insertion point of the arches, with a basiventral origin. The presence of ALP and Oc1, not only in cells outside the notochord, but also in the notochord epithelium, suggests an active role of the notochord in the mineralization process. The same may apply to Col II-positive chondrocytes of the caudalmost haemal arches that show ALP activity and Oc1 accumulation, since these chondrocytes do not mineralize their own cartilage matrix. Even without cartilaginous preformed vertebral centra, the cartilaginous arches may have an inductive role in vertebral centrum formation, possibly contributing to the distinct mineralization patterns of zebrafish vertebral column and caudal fin vertebral fusion. PMID:23043290

Distinct patterns of notochord mineralization in zebrafish coincide with the localization of Osteocalcin isoform 1 during early vertebral centra formation.

PubMed

Bensimon-Brito, Anabela; Cardeira, João; Cancela, Maria Leonor; Huysseune, Ann; Witten, Paul Eckhard

2012-10-09

In chondrichthyans, basal osteichthyans and tetrapods, vertebral bodies have cartilaginous anlagen that subsequently mineralize (chondrichthyans) or ossify (osteichthyans). Chondrocytes that form the vertebral centra derive from somites. In teleost fish, vertebral centrum formation starts in the absence of cartilage, through direct mineralization of the notochord sheath. In a second step, the notochord is surrounded by somite-derived intramembranous bone. In several small teleost species, including zebrafish (Danio rerio), even haemal and neural arches form directly as intramembranous bone and only modified caudalmost arches remain cartilaginous. This study compares initial patterns of mineralization in different regions of the vertebral column in zebrafish. We ask if the absence or presence of cartilaginous arches influences the pattern of notochord sheath mineralization. To reveal which cells are involved in mineralization of the notochord sheath we identify proliferating cells, we trace mineralization on the histological level and we analyze cell ultrastructure by TEM. Moreover, we localize proteins and genes that are typically expressed by skeletogenic cells such as Collagen type II, Alkaline phosphatase (ALP) and Osteocalcin (Oc). Mineralization of abdominal and caudal vertebrae starts with a complete ring within the notochord sheath and prior to the formation of the bony arches. In contrast, notochord mineralization of caudal fin centra starts with a broad ventral mineral deposition, associated with the bases of the modified cartilaginous arches. Similar, arch-related, patterns of mineralization occur in teleosts that maintain cartilaginous arches throughout the spine.Throughout the entire vertebral column, we were able to co-localize ALP-positive signal with chordacentrum mineralization sites, as well as Collagen II and Oc protein accumulation in the mineralizing notochord sheath. In the caudal fin region, ALP and Oc signals were clearly produced both by the notochord epithelium and cells outside the notochord, the cartilaginous arches. Based on immunostaining, real time PCR and oc2:gfp transgenic fish, we identify Oc in the mineralizing notochord sheath as osteocalcin isoform 1 (Oc1). If notochord mineralization occurs prior to arch formation, mineralization of the notochord sheath is ring-shaped. If notochord mineralization occurs after cartilaginous arch formation, mineralization of the notochord sheath starts at the insertion point of the arches, with a basiventral origin. The presence of ALP and Oc1, not only in cells outside the notochord, but also in the notochord epithelium, suggests an active role of the notochord in the mineralization process. The same may apply to Col II-positive chondrocytes of the caudalmost haemal arches that show ALP activity and Oc1 accumulation, since these chondrocytes do not mineralize their own cartilage matrix. Even without cartilaginous preformed vertebral centra, the cartilaginous arches may have an inductive role in vertebral centrum formation, possibly contributing to the distinct mineralization patterns of zebrafish vertebral column and caudal fin vertebral fusion.

The insulin-like growth factor I system: physiological and pathophysiological implication in cardiovascular diseases associated with metabolic syndrome.

PubMed

Ren, Jun; Anversa, Piero

2015-02-15

Metabolic syndrome is a cluster of risk factors including obesity, dyslipidemia, hypertension, and insulin resistance. A number of theories have been speculated for the pathogenesis of metabolic syndrome including impaired glucose and lipid metabolism, lipotoxicity, oxidative stress, interrupted neurohormonal regulation and compromised intracellular Ca(2+) handling. Recent evidence has revealed that adults with severe growth hormone (GH) and insulin-like growth factor I (IGF-1) deficiency such as Laron syndrome display increased risk of stroke and cardiovascular diseases. IGF-1 signaling may regulate contractility, metabolism, hypertrophy, apoptosis, autophagy, stem cell regeneration and senescence in the heart to maintain cardiac homeostasis. An inverse relationship between plasma IGF-1 levels and prevalence of metabolic syndrome as well as associated cardiovascular complications has been identified, suggesting the clinical promises of IGF-1 analogues or IGF-1 receptor activation in the management of metabolic and cardiovascular diseases. However, the underlying pathophysiological mechanisms between IGF-1 and metabolic syndrome are still poorly understood. This mini-review will discuss the role of IGF-1 signaling cascade in the prevalence of metabolic syndrome in particular the susceptibility to overnutrition and sedentary life style-induced obesity, dyslipidemia, insulin resistance and other features of metabolic syndrome. Special attention will be dedicated in IGF-1-associated changes in cardiac responses in various metabolic syndrome components such as insulin resistance, obesity, hypertension and dyslipidemia. The potential risk of IGF-1 and IGF-1R stimulation such as tumorigenesis is discussed. Therapeutic promises of IGF-1 and IGF-1 analogues including mecasermin, mecasermin rinfabate and PEGylated IGF-1 will be discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

Maxillary dental arch dimensions in 6-year-old children with articulatory speech disorders.

PubMed

Heliövaara, Arja

2011-01-01

To evaluate maxillary dental arch dimensions in 6-year-old children with articulatory speech disorders and to compare their dental arch dimensions with age- and sex-matched controls without speech disorders. Fifty-two children (15 girls) with errors in the articulation of the sounds /r/, /s/ or /l/ were compared retrospectively with age- and sex-matched controls from dental casts taken at a mean age of 6.4 years (range 5.0-8.4). All children with articulatory speech disorders had been referred to City of Helsinki Health Care, Dental Care Department by a phoniatrician or a speech therapist in order to get oral-motor activators (removable palatal plates) to be used in their speech therapy. A χ2-test and paired Student's t tests were used in the statistical analyses. The children with articulatory speech disorders had similar maxillary dental arch widths but smaller maxillary dental arch length than the controls. This small series suggests that 6-year-old children with articulatory speech disorders may have decreased maxillary dental arch length. Copyright © 2011 S. Karger AG, Basel.

NASA ARCH- A FILE ARCHIVAL SYSTEM FOR THE DEC VAX

NASA Technical Reports Server (NTRS)

Scott, P. J.

1994-01-01

The function of the NASA ARCH system is to provide a permanent storage area for files that are infrequently accessed. The NASA ARCH routines were designed to provide a simple mechanism by which users can easily store and retrieve files. The user treats NASA ARCH as the interface to a black box where files are stored. There are only five NASA ARCH user commands, even though NASA ARCH employs standard VMS directives and the VAX BACKUP utility. Special care is taken to provide the security needed to insure file integrity over a period of years. The archived files may exist in any of three storage areas: a temporary buffer, the main buffer, and a magnetic tape library. When the main buffer fills up, it is transferred to permanent magnetic tape storage and deleted from disk. Files may be restored from any of the three storage areas. A single file, multiple files, or entire directories can be stored and retrieved. archived entities hold the same name, extension, version number, and VMS file protection scheme as they had in the user's account prior to archival. NASA ARCH is capable of handling up to 7 directory levels. Wildcards are supported. User commands include TEMPCOPY, DISKCOPY, DELETE, RESTORE, and DIRECTORY. The DIRECTORY command searches a directory of savesets covering all three archival areas, listing matches according to area, date, filename, or other criteria supplied by the user. The system manager commands include 1) ARCHIVE- to transfer the main buffer to duplicate magnetic tapes, 2) REPORTto determine when the main buffer is full enough to archive, 3) INCREMENT- to back up the partially filled main buffer, and 4) FULLBACKUP- to back up the entire main buffer. On-line help files are provided for all NASA ARCH commands. NASA ARCH is written in DEC VAX DCL for interactive execution and has been implemented on a DEC VAX computer operating under VMS 4.X. This program was developed in 1985.

Aortic Arch Morphology and Aortic Length in Patients with Dissection, Traumatic, and Aneurysmal Disease.

PubMed

Alberta, H B; Takayama, T; Smits, T C; Wendorff, B B; Cambria, R P; Farber, M A; Jordan, W D; Patel, V; Azizzadeh, A; Rovin, J D; Matsumura, J S

2015-12-01

To assess aortic arch morphology and aortic length in patients with dissection, traumatic injury, and aneurysm undergoing TEVAR, and to identify characteristics specific to different pathologies. This was a retrospective analysis of the aortic arch morphology and aortic length of dissection, traumatic injury, and aneurysmal patients. Computed tomography imaging was evaluated of 210 patients (49 dissection, 99 traumatic injury, 62 aneurysm) enrolled in three trials that received the conformable GORE TAG thoracic endoprosthesis. The mean age of trauma patients was 43 ± 19.6 years, 57 ± 11.7 years for dissection and 72 ± 9.6 years for aneurysm patients. A standardized protocol was used to measure aortic arch diameter, length, and take-off angle and clockface orientation of branch vessels. Differences in arch anatomy and length were assessed using ANOVA and independent t tests. Of the 210 arches evaluated, 22% had arch vessel common trunk configurations. The aortic diameter and the distance from the left main coronary (LMC) to the left common carotid (LCC) were greater in dissection patients than in trauma or aneurysm patients (p < .001). Aortic diameter in aneurysm patients was greater compared with trauma patients (p < .05). The distances from the branch vessels to the celiac artery (CA) were greater in dissection and aneurysm patients than in trauma patients (p < .001). The take-off angle of the innominate (I), LCCA, and left subclavian (LS) were greater, between 19% and 36%, in trauma patients than in dissection and aneurysm patients (p < .001). Clockface orientation of the arch vessels varies between pathologies. Arch anatomy has significant morphologic differences when comparing aortic pathologies. Describing these differences in a large sample of patients is beneficial for device designs and patient selection. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Advantages of a Beveled Osteotomy on the Zygomatic Arch During Reduction Malarplasty.

PubMed

Lee, Tae Sung; Park, Sanghoon

2017-10-01

During a conventional reduction malarplasty procedure, a dual approach including intraoral incisions and preauricular incisions is made to reduce both the zygomatic body and arch. As the preauricular approach is performed to cut the zygomatic arch, there are several remarkable advantages that can be achieved by simply beveling the osteotomy anteriorly on the zygomatic arch. This has the benefits of enhancing bone union by the increase in cross-sectional area for bone contact, decreasing palpability on the osteotomy site, placing the osteotomy more posteriorly, preventing depression in the anterior malar region, and reducing the need for metal fixtures.

Arched-outer-race ball-bearing analysis considering centrifugal forces

NASA Technical Reports Server (NTRS)

Hamrock, B. J.; Anderson, W. J.

1972-01-01

A first-order thrust load analysis that considers centrifugal forces but which neglects gyroscopics, elastohydrodynamics, and thermal effects was performed. The analysis was applied to a 150-mm-bore angular-contact ball bearing. Fatigue life, contact loads, and contact angles are shown for conventional and arched bearings. The results indicate that an arched bearing is highly desirable for high-speed applications. In particular, at an applied load of 4448 n (1000 lb) and a DN value of 3 million (20,000 rpm) the arched bearing shows an improvement in life of 306 percent over that of a conventional bearing.

A socio-technical systems approach to studying interruptions: understanding the interrupter's perspective.

PubMed

Rivera, A Joy

2014-05-01

The purpose of this study was to understand the cognitive processes underlying nurses' decision to interrupt other nurses. The Institute of Medicine (2000) reported that interruptions are likely contributors to medical errors. Unfortunately, the research to date has been quite homogenous, focusing only on the healthcare provider being interrupted, ignoring the true complexities of interruptions. This study took a socio-technical approach being the first to examine interruptions from the viewpoint of the interrupting nurse. Over 15 h of observations and 10 open-ended interviews with expert nurses in a Neuroscience Surgical Intensive Care Unit were conducted. It was found that nurses conduct a quick cost-benefit assessment to determine the interruptibility of other nurses and whether an interruption is value-added vs. non-value added. To complete the assessment, nurses consider several conditional factors related to the interruptee, the interrupter, and the nature of the interruption content, and different potential consequences of the interruption. Published by Elsevier Ltd.

Developmental and evolutionary significance of the mandibular arch and prechordal/premandibular cranium in vertebrates: revising the heterotopy scenario of gnathostome jaw evolution

PubMed Central

Kuratani, Shigeru; Adachi, Noritaka; Wada, Naoyuki; Oisi, Yasuhiro; Sugahara, Fumiaki

2013-01-01

The cephalic neural crest produces streams of migrating cells that populate pharyngeal arches and a more rostral, premandibular domain, to give rise to an extensive ectomesenchyme in the embryonic vertebrate head. The crest cells forming the trigeminal stream are the major source of the craniofacial skeleton; however, there is no clear distinction between the mandibular arch and the premandibular domain in this ectomesenchyme. The question regarding the evolution of the gnathostome jaw is, in part, a question about the differentiation of the mandibular arch, the rostralmost component of the pharynx, and in part a question about the developmental fate of the premandibular domain. We address the developmental definition of the mandibular arch in connection with the developmental origin of the trabeculae, paired cartilaginous elements generally believed to develop in the premandibular domain, and also of enigmatic cartilaginous elements called polar cartilages. Based on comparative embryology, we propose that the mandibular arch ectomesenchyme in gnathostomes can be defined as a Dlx1-positive domain, and that the polar cartilages, which develop from the Dlx1-negative premandibular ectomesenchyme, would represent merely posterior parts of the trabeculae. We also show, in the lamprey embryo, early migration of mandibular arch mesenchyme into the premandibular domain, and propose an updated version of the heterotopy theory on the origin of the jaw. PMID:22500853

Stratigraphic variations in the Carboniferous section across the Arkansas-Oklahoma State Line Arch

NASA Astrophysics Data System (ADS)

Engelhardt, Tyler D.

The State Line Arch is represented by a structural high that trends through the study area in a loose alignment with the Arkansas-Oklahoma state line. Evidence of the arch extending further to the north includes a structural high and stratigraphic variation at an outcrop on Highway 59 near Evansville Mountain in Crawford County, Arkansas. The exact timing of the formation of the arch remains undetermined, but upper Devonian thinning at the top of the arch indicates the structure is pre-Mississippian. The reason for the development of the arch is poorly understood, but evidence linking Mississippian-aged Waulsortian mounds to Precambrian Spavinaw granite structures of northeastern Oklahoma and southwestern Missouri suggests Precambrian basement structures may extend into the study area. The structural nature of the arch provided an environment favorable to carbonate build-up during deposition of the Mississippian interval. A previously unidentified limestone unit measuring 175 feet thick likely represents the transgressive phase of a transgressive-regressive sequence responsible for the deposition of the Mayes Group of northeastern Oklahoma. Growth on the downthrown side of the Muldrow-Mulberry Fault system may indicate earlier movement than previous studies have suggested on the east-west trending normal faults of the Arkoma Basin. A possible roll-over anticline structure may exist to the south of the Muldrow-Mulberry fault system.

Angiotensin converting enzyme inhibitors and aortic arch obstructive malformations.

PubMed

Maliheh, Kadivar; Abdorrazagh, Kiani; Armen, Kocharian; Reza, Shabanian

2006-10-01

We describe two newborn infants with aortic arch obstructive malformations who became anuric after initiation of captopril. Since angiotensin converting enzyme inhibitors can alter renal blood flow by reduction in angiotensin II and blocking autoregulation phenomenon, it is important to use them with great caution in neonates with aortic arch obstructive malformations, while monitoring their renal function closely.

Influences on Early and Medium-Term Survival Following Surgical Repair of the Aortic Arch

PubMed Central

Bashir, Mohamad; Field, Mark; Shaw, Matthew; Fok, Matthew; Harrington, Deborah; Kuduvalli, Manoj; Oo, Aung

2014-01-01

Objectives: It is now well established by many groups that surgery on the aortic arch may be achieved with consistently low morbidity and mortality along with relatively good survival compared to estimated natural history for a number of aortic arch pathologies. The objectives of this study were to: 1) report, compare, and analyze our morbidity and mortality outcomes for hemiarch and total aortic arch surgery; 2) examine the survival benefit of hemiarch and total aortic arch surgery compared to age- and sex-matched controls; and 3) define factors which influence survival in these two groups and, in particular, identify those that are modifiable and potentially actionable. Methods: Outcomes from patients undergoing surgical resection of both hemiarch and total aortic arch at the Liverpool Heart and Chest Hospital between June 1999 and December 2012 were examined in a retrospective analysis of data collected for The Society for Cardiothoracic Surgeons (UK). Results: Over the period studied, a total of 1240 patients underwent aortic surgery, from which 287 were identified as having undergone hemi to total aortic arch surgery under deep or moderate hypothermic circulatory arrest. Twenty three percent of patients' surgeries were nonelective. The median age at the time of patients undergoing elective hemiarch was 64.3 years and total arch was 65.3 years (P = 0.25), with 40.1% being female in the entire group. A total of 140 patients underwent elective hemiarch replacement, while 81 underwent elective total arch replacement. Etiology of the aortic pathology was degenerative in 51.2% of the two groups, with 87.1% requiring aortic valve repair in the elective hemiarch group and 64.2% in the elective total arch group (P < 0.001). Elective in-hospital mortality was 2.1% in the hemiarch group and 6.2% (P = 0.15) in the total arch group with corresponding rates of stroke (2.9% versus 4.9%, P = 0.47), renal failure (4.3% versus 6.2%, P = 0.54), reexploration for bleeding (4.3% versus 4.9%, P > 0.99), and prolonged ventilation (8.6% versus 16.1%, P = 0.09). Overall mortality was 20.9% at 5 years, while it was 15.7% in the elective hemiarch and 25.9% in the total arch group (P = 0.065). Process control charts demonstrated stability of annualized mortality outcomes over the study period. Survival curve was flat and parallel compared to age- and sex-matched controls beyond 2 years. Multivariate analysis demonstrated the following independent factors associated with survival: renal dysfunction [hazard ratio (HR) = 3.11; 95% confidence interval (CI) = 1.44-6.73], New York Heart Association (NYHA) class ≥ III (HR = 2.25; 95% CI = 1.38-3.67), circulatory arrest time > 100 minutes (HR = 2.92; 95% CI = 1.57-5.43), peripheral vascular disease (HR = 2.44; 95% CI = 1.25-4.74), and concomitant coronary artery bypass graft operation (HR = 2.14; 95% CI = 1.20-3.80). Conclusions: Morbidity, mortality, and medium-term survival were not statistically different for patients undergoing elective hemi-aortic arch and total aortic arch surgery. The survival curve in this group of patients is flat and parallel to sex- and age-matched controls beyond 2 years. Multivariate analysis identified independent influences on survival as renal dysfunction, NYHA class ≥ III, circulatory arrest time (> 100 min), peripheral vascular disease, and concomitant coronary artery bypass grafting. Focus on preoperative optimization of some of these variables may positively influence long-term survival. PMID:26798716

[Biomechanical testing of the new torque-segmented arch (TSA)].

PubMed

Wichelhaus, A; Sander, F G

1995-07-01

New torque-segmented arch wires are presented which consist of a superelastic anterior component with 30 degrees or 45 degrees torque and which are connected to 2 steel lateral components by means of a crimped connector. When using such torque-segmented arch wires, the crimped connector rests mesially to the canine bracket and the lateral components exhibit a torque of 0 degree. The use of the torque-segmented arch wires requires the practitioner to adjust the anterior tooth segment, to bend in first order bends in the steel lateral portion as well as to bend in a sweep to avoid an anterior tooth extrusion, and, if desired, to bend in third order bends to influence premolars and molars. In some cases the simultaneous application of palatal arches can become necessary, because each torque transfer results in a transversal enlargement in the molar area. Compared to conventional steel wires with dimensions of 0.016 x 0.022 in which an anterior tooth torque is bent, the torque segmented arch wires exhibit considerably fewer side effects, but there is a larger distally rotating moment for the molars. 1. When applying torque-segmented arch wires, the extrusive force transferred to the anterior teeth is considerably smaller. 2. The protrusive force acting on the anterior teeth is also considerably smaller, which results in a reduced demand being placed on the anchorage of the molars. 3. The torque transfer to the incisors rests in a quite moderate range, even in the case of a 50 degrees torque. For this reason, the practitioner can expect diminished or no resorptions at all compared to the aforementioned steel wires. 4. The Martensite plateau of the torque-segmented arch wires exhibit constant moments in large areas so that such arch wires can be used in almost every anterior tooth position. 5. The segmented wires presented here can be applied not only in the case of the standard edgewise technique but also in each case of the straight-wire technique. 6. These new arch wires require no readjustment of torque values. 7. To control the transferred torque values it is recommended that the already transferred torque values be monitored during each check-up with the help of the described torque key. 8. When the torque values of the brackets are known, the torque key renders frequent patient X-rays superfluous. 9. When the desired torque values are attained, treatment can proceed using conventional arch wires.

A comparison of foot kinematics in people with normal- and flat-arched feet using the Oxford Foot Model.

PubMed

Levinger, Pazit; Murley, George S; Barton, Christian J; Cotchett, Matthew P; McSweeney, Simone R; Menz, Hylton B

2010-10-01

Foot posture is thought to influence predisposition to overuse injuries of the lower limb. Although the mechanisms underlying this proposed relationship are unclear, it is thought that altered foot kinematics may play a role. Therefore, this study was designed to investigate differences in foot motion between people with normal- and flat-arched feet using the Oxford Foot Model (OFM). Foot posture in 19 participants was documented as normal-arched (n=10) or flat-arched (n=9) using a foot screening protocol incorporating measurements from weightbearing antero-posterior and lateral foot radiographs. Differences between the groups in triplanar motion of the tibia, rearfoot and forefoot during walking were evaluated using a three-dimensional motion analysis system incorporating a multi-segment foot model (OFM). Participants with flat-arched feet demonstrated greater peak forefoot plantar-flexion (-13.7° ± 5.6° vs -6.5° ± 3.7°; p=0.004), forefoot abduction (-12.9° ± 6.9° vs -1.8° ± 6.3°; p=0.002), and rearfoot internal rotation (10.6° ± 7.5° vs -0.2°± 9.9°; p=0.018) compared to those with normal-arched feet. Additionally, participants with flat-arched feet demonstrated decreased peak forefoot adduction (-7.0° ± 9.2° vs 5.6° ± 7.3°; p=0.004) and a trend towards increased rearfoot eversion (-5.8° ± 4.4° vs -2.5° ± 2.6°; p=0.06). These findings support the notion that flat-arched feet have altered motion associated with greater pronation during gait; factors that may increase the risk of overuse injury. Copyright © 2010 Elsevier B.V. All rights reserved.

Contemporary results of open aortic arch surgery.

PubMed

Thomas, Mathew; Li, Zhuo; Cook, David J; Greason, Kevin L; Sundt, Thoralf M

2012-10-01

The success of endovascular therapies for descending thoracic aortic disease has turned attention toward stent graft options for repair of aortic arch aneurysms. Defining the role of such techniques demands understanding of contemporary results of open surgery. The outcomes of open arch procedures performed on a single surgical service from July 1, 2001 to August 30, 2010, were examined as defined per The Society of Thoracic Surgeons national database. During the study period, 209 patients (median age, 65 years; range, 26-88) underwent arch operations, of which 159 were elective procedures. In 65 the entire arch was replaced, 22 of whom had portions of the descending thoracic aorta simultaneously replaced via bilateral thoracosternotomy. Antegrade cerebral perfusion was used in 78 patients and retrograde cerebral perfusion in 1. Operative mortality was 2.5% in elective circumstances and 10% in emergency cases (P = .04). The stroke rate was 5.0% when procedures were performed electively and 11.8% when on an emergency basis (P = .11). Procedure-specific mortality rates were 5.5% for elective and 10% for emergency procedures with total arch replacement, and 1.0% for elective and 10% for emergency procedures with hemiarch replacement. Stratified by extent, neurologic event rates were 5.5% for elective and 10% for emergency procedures with total arch and 4.8% for elective and 12.5% for emergency procedures with hemiarch replacement. Open aortic arch replacement can be performed with low operative mortality and stroke rates, especially in elective circumstances, by a team with particular focus on the procedure. The results of novel endovascular therapies should be benchmarked against contemporary open series performed in such a setting. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

The effect of arch height on kinematic coupling during walking.

PubMed

Wilken, Jason; Rao, Smita; Saltzman, Charles; Yack, H John

2011-03-01

The purpose of the current study was to assess kinematic coupling within the foot in individuals across a range of arch heights. Seventeen subjects participated in this study. Weight-bearing lateral radiographs were used to measure the arch height, defined as angle between the 1st metatarsal and the calcaneus. A kinematic model including the 1st metatarsal, lateral forefoot, calcaneus and tibia was used to assess foot kinematics during walking. Four coupling ratios were calculated: calcaneus frontal to forefoot transverse plane motion (Calcaneal EV/Forefoot AB), calcaneus frontal to transverse plane motion (Calcaneus EV/AB), forefoot sagittal to transverse plane motion (Forefoot DF/AB), and 1st metatarsal sagittal to transverse plane motion (1st Metatarsal DF/AB). Pearson product moment correlations were used to assess the relationship between arch height and coupling ratios. Mean (SD) radiographic arch angles of 129.8 (12.1) degrees with a range from 114 to 153 were noted, underscoring the range of arch heights in this cohort. Arch height explained approximately 3%, 38%, 12% and 1% of the variance in Calcaneal EV/Forefoot AB, Calcaneus EV/AB, Forefoot DF/AB and 1st Metatarsal DF/AB respectively. Calcaneal EV/Forefoot AB, Calcaneus EV/AB, Forefoot DF/AB and 1st Metatarsal DF/AB coupling ratios of 1.84 ± 0.80, 0.56 ± 0.35, 0.96 ± 0.27 and 0.43 ± 0.21 were noted, consistent with the twisted foot plate model, windlass mechanism and midtarsal locking mechanisms. Arch height had a small and modest relationship with kinematic coupling ratios during walking. Copyright © 2010 Elsevier Ltd. All rights reserved.

Impact of Retrograde Arch Extension in Acute Type B Aortic Dissection on Management and Outcomes.

PubMed

Nauta, Foeke J H; Tolenaar, Jip L; Patel, Himanshu J; Appoo, Jehangir J; Tsai, Thomas T; Desai, Nimesh D; Montgomery, Daniel G; Mussa, Firas F; Upchurch, Gilbert R; Fattori, Rosella; Hughes, G Chad; Nienaber, Christoph A; Isselbacher, Eric M; Eagle, Kim A; Trimarchi, Santi

2016-12-01

Optimal management of acute type B aortic dissection with retrograde arch extension is controversial. The effect of retrograde arch extension on operative and long-term mortality has not been studied and is not incorporated into clinical treatment pathways. The International Registry of Acute Aortic Dissection was queried for all patients presenting with acute type B dissection and an identifiable primary intimal tear. Outcomes were stratified according to management for patients with and without retrograde arch extension. Kaplan-Meier survival curves were constructed. Between 1996 and 2014, 404 patients (mean age, 63.3 ± 13.9 years) were identified. Retrograde arch extension existed in 67 patients (16.5%). No difference in complicated presentation was noted (36.8% vs 31.7%, p = 0.46), as defined by limb or organ malperfusion, coma, rupture, and shock. Patients with or without retrograde arch extension received similar treatment, with medical management in 53.7% vs 56.5% (p = 0.68), endovascular treatment in 32.8% vs 31.1% (p = 0.78), open operation in 11.9% vs 9.5% (p = 0.54), or hybrid approach in 1.5% vs 3.0% (p = 0.70), respectively. The in-hospital mortality rate was similar for patients with (10.7%) and without (10.4%) retrograde arch extension (p = 0.96), and 5-year survival was also similar at 78.3% and 77.8%, respectively (p = 0.27). The incidence of retrograde arch dissection involves approximately 16% of patients with acute type B dissection. In the International Registry of Acute Aortic Dissection, this entity seems not to affect management strategy or early and late death. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Dynamic effect of the tibialis posterior muscle on the arch of the foot during cyclic axial loading.

PubMed

Kamiya, Tomoaki; Uchiyama, Eiichi; Watanabe, Kota; Suzuki, Daisuke; Fujimiya, Mineko; Yamashita, Toshihiko

2012-11-01

The most common cause of acquired flatfoot deformity is tibialis posterior tendon dysfunction. The present study compared the change in medial longitudinal arch height during cyclic axial loading with and without activated tibialis posterior tendon force. Fourteen normal, fresh frozen cadaveric legs were used. A total of 10,000 cyclic axial loadings of 500 N were applied to the longitudinal axis of the tibia. The 32-N tibialis posterior tendon forces were applied to the specimens of the active group (n=7). Specimens of another group (non-active group, n=7) were investigated without the tibialis posterior tendon force. The bony arch index was calculated from the displacement of the navicular height. The mean initial bony arch indexes with maximal weightbearing were 0.239 (SD 0.009) in active group and 0.239 (SD 0.014) in non-active group. After 7000 cycles, the bony arch indexes with maximal weightbearing were significantly greater in the active group (mean 0.214, SD 0.013) than in the non-active group (mean 0.199, SD 0.013). The mean bony arch indexes with maximal weightbearing after 10,000 cycles were 0.212 (SD 0.011) in the active group and 0.196 (SD 0.015) in the non-active group. The passive supportive structures were inadequate, and the tibialis posterior muscle was essential to maintain the medial longitudinal arch of the foot in the dynamic weightbearing condition. The findings underscore that physical therapy and arch supportive equipments are important to prevent flatfoot deformity in the condition of weakness or dysfunction of the tibialis posterior muscle. Copyright © 2012 Elsevier Ltd. All rights reserved.

Pathogenesis of solitary right aortic arch: a mass effect hypothesis based on observations of serial human embryonic sections.

PubMed

Jin, Zhe W; Yamada, Tomonori; Kim, Ji H; Rodríguez-Vázquez, José F; Murakami, Gen; Arakawa, Keiji

2017-03-01

In general, solitary right aortic arch carries the left-sided ductus arteriosus communicating between the left subclavian and pulmonary arteries or the right-sided ductus connecting the descending aorta to the left pulmonary artery. Serial sections of fifteen 5- to 6-week-old embryos and ten 8- to 9-week-old fetuses suggested that the pathogenesis was unrelated to inversion due to dysfunction in gene cascades that control the systemic left/right axis. With inversion, conversely, the ductus or the sixth pharyngeal arch artery should connect to the right pulmonary artery. The disappearance of the right aortic arch started before the caudal migration of the aortic attachment of the ductus. Sympathetic nerve ganglia developed immediately posterior to both aortae, with a single embryonic specimen showing a large ganglion at the midline close to the union of the aortic arches. These ganglia may interfere with blood flow through the distal left arch, resulting in the ductus ending at the descending aorta behind the oesophagus. In another fetus examined, a midline shift of the ductus course resulted in the trachea curving posteriorly. Therefore, solitary right arch is likely to accompany abnormalities of the surrounding structures. The timing and site of the obstruction should be different between types: an almost midline obstruction near the aortic union needed for the development of the left-sided ductus and a distal obstruction near the left subclavian arterial origin needed for the development of the right-sided ductus. A mass effect of the sympathetic ganglia may explain the pathogenesis of any type of anomalous ductus arteriosus shown in previous reports of the solitary right arch.

Simple retrograde cerebral perfusion is as good as complex antegrade cerebral perfusion for hemiarch replacement.

PubMed

Tanaka, Akiko; Estrera, Anthony L

2018-01-01

Cerebral complication is a major concern after aortic arch surgery, which may lead to death. Thus, cerebral protection strategy plays the key role to obtain respectable results in aortic arch repair. Deep hypothermic circulatory arrest was introduced in 1970s to decrease the ischemic insults to the brain. However, safe duration of circulatory arrest time was limited to 30 minutes. The 1990s was the decade of evolution for cerebral protection, in which two adjuncts for deep hypothermic circulatory arrest were introduced: retrograde and antegrade cerebral perfusion (ACP) techniques. These two cerebral perfusion techniques significantly decreased incidence of postoperative neurological dysfunction and mortality after aortic arch surgery. Although there are no large prospective studies that demonstrate which perfusion technique provide better outcomes, multiple retrospective studies implicate that ACP may decrease cerebral complications compared to retrograde cerebral perfusion (RCP) when a long circulatory arrest time is required during aortic arch reconstructions. To date, many surgeons favor ACP over RCP during a complex aortic arch repair, such as total arch replacement and hybrid arch replacement. However, the question is whether the use of ACP is necessary during a short, limited circulatory arrest time, such as hemiarch replacement? There is a paucity of data that proves the advantages of a complex ACP over a simple RCP for a short circulatory arrest time. RCP with deep hypothermic circulatory arrest is the simple, efficient cerebral protection technique with minimal interference to the surgical field-and it potentially allows to flush atheromatous debris out from the arch vessels. Thus, it is the preferred adjunct to deep hypothermic circulatory arrest during hemiarch replacement in our institution.

Simple retrograde cerebral perfusion is as good as complex antegrade cerebral perfusion for hemiarch replacement

PubMed Central

Tanaka, Akiko

2018-01-01

Cerebral complication is a major concern after aortic arch surgery, which may lead to death. Thus, cerebral protection strategy plays the key role to obtain respectable results in aortic arch repair. Deep hypothermic circulatory arrest was introduced in 1970s to decrease the ischemic insults to the brain. However, safe duration of circulatory arrest time was limited to 30 minutes. The 1990s was the decade of evolution for cerebral protection, in which two adjuncts for deep hypothermic circulatory arrest were introduced: retrograde and antegrade cerebral perfusion (ACP) techniques. These two cerebral perfusion techniques significantly decreased incidence of postoperative neurological dysfunction and mortality after aortic arch surgery. Although there are no large prospective studies that demonstrate which perfusion technique provide better outcomes, multiple retrospective studies implicate that ACP may decrease cerebral complications compared to retrograde cerebral perfusion (RCP) when a long circulatory arrest time is required during aortic arch reconstructions. To date, many surgeons favor ACP over RCP during a complex aortic arch repair, such as total arch replacement and hybrid arch replacement. However, the question is whether the use of ACP is necessary during a short, limited circulatory arrest time, such as hemiarch replacement? There is a paucity of data that proves the advantages of a complex ACP over a simple RCP for a short circulatory arrest time. RCP with deep hypothermic circulatory arrest is the simple, efficient cerebral protection technique with minimal interference to the surgical field—and it potentially allows to flush atheromatous debris out from the arch vessels. Thus, it is the preferred adjunct to deep hypothermic circulatory arrest during hemiarch replacement in our institution. PMID:29682460

Analysis of the dentoalveolar effects of slow and rapid maxillary expansion in complete bilateral cleft lip and palate patients: a randomized clinical trial.

PubMed

de Medeiros Alves, Arthur César; Garib, Daniela Gamba; Janson, Guilherme; de Almeida, Araci Malagodi; Calil, Louise Resti

2016-09-01

The purpose of this study was to compare the dentoalveolar effects of slow (SME) and rapid (RME) maxillary expansions in patients with complete bilateral cleft lip and palate (BCLP). A sample of 50 patients with BCLP and maxillary arch constriction was randomly and equally allocated into two groups. Group SME comprised patients (mean age of 8.8 years) treated with quad-helix appliance. Group RME comprised individuals (mean age of 8.9 years) treated with Hyrax expander. Digital dental models obtained immediately pre-expansion (T1) and 6 months after the active expansion period (T2) were used for measuring maxillary dental arch widths, arch perimeter, arch length, palatal depth, buccolingual inclination of posterior teeth and differential amount of expansion accomplished at the canine and molar regions. Inter-phase and intergroup comparisons were performed using paired t tests and t tests, respectively (p < 0.05). SME and RME caused significant increase of arch widths and arch perimeter. Arch length and palatal depth decreased nonsignificantly with SME but significantly with RME. Buccal tooth inclination was significant only for maxillary deciduous canines in both groups. The quad-helix appliance showed a significant differential expansion between anterior and posterior regions. No differences were observed between SME and RME for all variables. Differences were not found between the dentoalveolar effects of SME and RME in patients with BCLP. SME demanded a greater therapy time compared to RME. Both expansion procedures can be similarly indicated to correct maxillary arch constriction in patients with BCLP in the mixed dentition.

Pulsatile flows and wall-shear stresses in models simulating normal and stenosed aortic arches

NASA Astrophysics Data System (ADS)

Huang, Rong Fung; Yang, Ten-Fang; Lan, Y.-K.

2010-03-01

Pulsatile aqueous glycerol solution flows in the models simulating normal and stenosed human aortic arches are measured by means of particle image velocimetry. Three transparent models were used: normal, 25% stenosed, and 50% stenosed aortic arches. The Womersley parameter, Dean number, and time-averaged Reynolds number are 17.31, 725, and 1,081, respectively. The Reynolds numbers based on the peak velocities of the normal, 25% stenosed, and 50% stenosed aortic arches are 2,484, 3,456, and 3,931, respectively. The study presents the temporal/spatial evolution processes of the flow pattern, velocity distribution, and wall-shear stress during the systolic and diastolic phases. It is found that the flow pattern evolving in the central plane of normal and stenosed aortic arches exhibits (1) a separation bubble around the inner arch, (2) a recirculation vortex around the outer arch wall upstream of the junction of the brachiocephalic artery, (3) an accelerated main stream around the outer arch wall near the junctions of the left carotid and the left subclavian arteries, and (4) the vortices around the entrances of the three main branches. The study identifies and discusses the reasons for the flow physics’ contribution to the formation of these features. The oscillating wall-shear stress distributions are closely related to the featured flow structures. On the outer wall of normal and slightly stenosed aortas, large wall-shear stresses appear in the regions upstream of the junction of the brachiocephalic artery as well as the corner near the junctions of the left carotid artery and the left subclavian artery. On the inner wall, the largest wall-shear stress appears in the region where the boundary layer separates.

Multi-objective optimization of an arch dam shape under static loads using an evolutionary game method

NASA Astrophysics Data System (ADS)

Meng, Rui; Cheong, Kang Hao; Bao, Wei; Wong, Kelvin Kian Loong; Wang, Lu; Xie, Neng-gang

2018-06-01

This article attempts to evaluate the safety and economic performance of an arch dam under the action of static loads. The geometric description of a crown cantilever section and the horizontal arch ring is presented. A three-objective optimization model of arch dam shape is established based on the arch dam volume, maximum principal tensile stress and total strain energy. The evolutionary game method is then applied to obtain the optimal solution. In the evolutionary game technique, a novel and more efficient exploration method of the game players' strategy space, named the 'sorting partition method under the threshold limit', is presented, with the game profit functions constructed according to both competitive and cooperative behaviour. By way of example, three optimization goals have all shown improvements over the initial solutions. In particular, the evolutionary game method has potentially faster convergence. This demonstrates the preliminary proof of principle of the evolutionary game method.

[The effect of modified Nance arch on treating maxillary impacted canine transposed with first premolar].

PubMed

Xu, Qing-chao; Sun, Hao; Lin, Yan; Wang, Xiu-ying; Hu, Rong-dang

2015-10-01

To explore the effect of modified Nance arch on treating maxillary canine-first premolar transposition cases, in which the anchorage and force direction were discussed. Modified Nance arch was applied to 5 cases with maxillary impacted canine-first premolar transposition. First, a lingual knot button was bonded on the surface of the canine crown. Modified Nance arch was decorated with a hook that moved horizontally and buccally. Then the location of the hook was gradually adjusted in order to move the canine cross the root of the first premolar and move the canine to the right position. At last the canine was moved downward by straight wire appliance. Five maxillary transposed canines were fully erupted in their right position, with normal pulp activity and gingival morphology. No obvious root resorption was detected. The mean treatment time was 30 months. Modified Nance arch has advantages in treating canine-first premolar transposition.

Collapse displacements for a mechanism of spreading-induced supports in a masonry arch

NASA Astrophysics Data System (ADS)

Coccia, Simona; Di Carlo, Fabio; Rinaldi, Zila

2015-09-01

Masonry arch systems and vaulted structures constitute a structural typology widely spread in the historical building heritage. Small displacements of the supports, due to different causes, among which subsidence of foundation systems or movements of underlying structures can lead the masonry arch to a condition of collapse because of gradual change in its geometry. This paper presents a tool, based on a kinematic approach, for the computation of the magnitude of the displacements that cause the collapse of circular arches subject to dead loads, and allows the evaluation of the related thrust value. A parametric study has been carried out in order to develop a deeper understanding of the influence of the involved parameters. In addition, analytic formulations of the maximum allowed displacement and the associated thrust are proposed. Finally, a case study related to the behavior of a masonry arch on spreading-induced abutments is undertaken and discussed.

Difficulties in distinguishing between an atlas fracture and a congenital posterior atlas arch defect in postmortem analysis.

PubMed

Sanchis-Gimeno, Juan A; Blanco-Perez, Esther; Aparicio, Luis; Martinez-Soriano, Francisco; Martinez-Sanjuan, Vicente

2014-09-01

We found one atlas from a sample of 148 skeletons (0.67%) that presented different anatomical variations which made it difficult to determine whether the vertebra had an atlas fracture, an unusual Type B posterior atlas arch defect, or a combination of both. We carried out a stereomicroscopy, radiographic, and computerized tomography scan study that revealed that the dry atlas we found presented a very uncommon congenital Type B posterior atlas arch defect, simulating a fracture. In short, the present paper has revealed that differentiating Type B posterior atlas arch defects from fractures in post-mortem dry vertebrae is more difficult than expected. Thus we believe that it can be easier than expected to mistake Type B posterior arch defects for fractures and vice versa in postmortem studies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Cortical bone thickening in Type A posterior atlas arch defects: experimental report.

PubMed

Sanchis-Gimeno, Juan A; Llido, Susanna; Guede, David; Martinez-Soriano, Francisco; Ramon Caeiro, Jose; Blanco-Perez, Esther

2017-03-01

To date, no information about the cortical bone microstructural properties in atlas vertebrae with posterior arch defects has been reported. To test if there is an increased cortical bone thickening in atlases with Type A posterior atlas arch defects in an experimental model. Micro-computed tomography (CT) study on cadaveric atlas vertebrae. We analyzed the cortical bone thickness, the cortical volume, and the medullary volume (SkyScan 1172 Bruker micro-CT NV, Kontich, Belgium) in cadaveric dry vertebrae with a Type A atlas arch defect and normal control vertebrae. The micro-CT study revealed significant differences in cortical bone thickness (p=.005), cortical volume (p=.003), and medullary volume (p=.009) values between the normal and the Type A vertebrae. Type A congenital atlas arch defects present a cortical bone thickening that may play a protective role against atlas fractures. Copyright © 2016 Elsevier Inc. All rights reserved.

Construction Simulation Analysis of 60m-span Concrete Filled Steel Tube arch bridge

NASA Astrophysics Data System (ADS)

Shi, Jing Xian; Ding, Qing Hua

2018-06-01

The construction process of the CFST arch bridge is complicated. The construction process not only affects the structural stress in the installation, but also determines the form a bridge and internal force of the bridge. In this paper, a 60m span concrete filled steel tube tied arch bridge is taken as the background, and a three-dimensional finite element simulation model is established by using the MIDAS/Civil bridge structure analysis software. The elevation of the main arch ring, the beam stress, the forces in hanger rods and the modal frequency of the main arch during the construction stage are calculated, and the construction process is simulated and analyzed. Effectively and reasonably guide the construction and ensure that the line and force conditions of the completed bridge meet the design requirements and provides a reliable technical guarantee for the safe construction of the bridge.

Association of conjunctival and corneal calcification with vascular calcification among hepatitis-C-seropositive hemodialysis patients.

PubMed

AbouSeif, Khaled; Sany, Dawlat; Elshahawy, Yasser; Seddik, Ayman; Rahman, Khedr; Gaber, Moustapha

2016-01-01

Disorders associated with the hepatitis C virus (HCV) have been reported including cardiovascular, metabolic, and central nervous system diseases. Since chronic HCV infections may be curable, their identification as causal contributors to cardiovascular risk could offer new perspectives in the prevention of cardiovascular disease. The aim of this study is to investigate the association between HCV and aortic arch calcification (AAC) and corneal and conjunctival calcification (CCC) in maintenance hemodialysis (MHD) patients; further, we assessed the correlation of CCC with vascular calcification. A total of 100 patients undergoing hemodialysis (HD) in our hospital were included in this study. Patients underwent a complete ocular examination including intraocular pressure, and CCC was looked for by slit lamp and fundoscopy. CCC was graded according to modified Porter and Crombie classification system described by Tokuyama et al. Helical computerized tomographic chest examination was used to evaluate the grading of AAC. Demographic, hematological, biochemical, and dialysis-related data were obtained. There was significant difference between seropositive (n = 51) and seronegative patients (n = 49) regarding grading of AAC and CCC (P <0.001). Significant positive correlation was found between grading of CCC, AAC, age (P <0.001), duration on HD (P <0.001), HCV-antibody positivity (P <0.001), serum calcium level (P <0.001), serum phosphorus level (P <0.001), calcium × phosphorus product (P <0.001), and i-parathormone level (P < 0.001). In addition, CCC grading positively correlated with AAC. Our results suggest that patients undergoing HD infected with the HCV have high degree of CCC, AAC, and mineral metabolism disorder. The strong correlation between CCC and AAC indicates that CCC evaluation is an easy, fast, non-invasive method, and might be used as an indirect indicator to detect vascular calcification in patients undergoing MHD.

Risk of Vascular Thrombotic Events Following Discontinuation of Antithrombotics After Peptic Ulcer Bleeding.

PubMed

Kim, Seung Young; Hyun, Jong Jin; Suh, Sang Jun; Jung, Sung Woo; Jung, Young Kul; Koo, Ja Seol; Yim, Hyung Joon; Park, Jong Jae; Chun, Hoon Jai; Lee, Sang Woo

2016-04-01

To evaluate whether the risk of cardiovascular events increases when antithrombotics are discontinued after ulcer bleeding. Peptic ulcer bleeding associated with antithrombotics has increased due to the increase in the proportion of elderly population. Little is known about the long-term effects of discontinuing antithrombotics after peptic ulcer bleeding. The aim of this study was to evaluate whether the risk of cardiovascular events increases when antithrombotics are discontinued after ulcer bleeding. We reviewed the medical records of patients with ulcer bleeding who were taking antiplatelet agents or anticoagulants at the time of ulcer bleeding. Cox-regression model was used to adjust for potential confounders, and analyzed association between discontinuation of antithrombotic drugs after ulcer bleeding and thrombotic events such as ischemic heart disease or stroke. Of the 544 patients with ulcer bleeding, 72 patients who were taking antithrombotics and followed up for >2 months were analyzed. Forty patients discontinued antithrombotics after ulcer bleeding (discontinuation group) and 32 patients continued antithrombotics with or without transient interruption (continuation group). Thrombotic events developed more often in discontinuation group than in the continuation group [7/32 (21.9%) vs. 1/40 (2.5%), P=0.019]. Hazard ratio for thrombotic event when antithrombotics were continuously discontinued was 10.9 (95% confidence interval, 1.3-89.7). There were no significant differences in recurrent bleeding events between the 2 groups. Discontinuation of antithrombotics after peptic ulcer bleeding increases the risk of cardiovascular events. Therefore, caution should be taken when discontinuing antithrombotics after ulcer bleeding.

Maxillary Arch Dimensions and Spectral Characteristics of Children with Cleft Lip and Palate Who Produce Middorsum Palatal Stops

ERIC Educational Resources Information Center

Zajac, David J.; Cevidanes, Lucia; Shah, Sonam; Haley, Katarina L.

2012-01-01

Purpose: The purpose of this study was twofold: (a) to determine maxillary arch dimensions of children with repaired cleft lip and palate (CLP) who produced middorsum palatal stops and (b) to describe some spectral characteristics of middorsum palatal stops. Method: Maxillary arch width, length, and height dimensions and first spectral moments of…

Lateral testing of glued laminated timber tudor arch

Treesearch

Douglas R. Rammer; Philip Line

2016-01-01

Glued laminated timber Tudor arches have been in wide use in the United States since the 1930s, but detailed knowledge related to seismic design in modern U.S. building codes is lacking. FEMA P-695 (P-695) is a methodology to determine seismic performance factors for a seismic force resisting system. A limited P-695 study for glued laminated timber arch structures...

Copy image of "'Under the Great Arch' of Refectory Bridge ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Copy image of "'Under the Great Arch' of Refectory Bridge connecting the Dining Room with the Practice House, Delta, and the Villa. The Refectory Cloister is seen beyond the arch"; a similar, but recent, view can be seen in MD-1109-A-16. (NPS view book, p. 25) - National Park Seminary, Main, Linden Lane, Silver Spring, Montgomery County, MD

Ultraviolet Events Observed in Active Regions. 2; An Interpretation of Flaring Arches and Associated Small Flares

NASA Technical Reports Server (NTRS)

Fontenla, J.; Rovira, M.; Tandberg-Hanssen, E.

1997-01-01

We analyze Hz, UV, and X-ray emissions in and around the spectacular arch system seen in the corona on 1980 March 27 during the Solar Maximum Mission. The flaring of the arch plasma is studied, and its dependence on triggering mechanisms related to the observed small limb flare in the arch footpoint is analyzed. To drive these events, we propose a mechanism in which small electric current circuits and the localized magnetic free energy are continuously generated at a magnetic null by a pressure gradient, which then compress or expand the plasma. This free energy dissipates by Joule effect and upward transport.

[Foot arch shape in children aged 2-5 years according to the data of plantography and holographic interferometry].

PubMed

bol'shakov, O P; Kotov, I R; Poliakova, E L

2014-01-01

25 children aged 2 to 5 years were examined orthopedically using the methods of plantometry and holographic interferometry of three-dimensional casts of footprints. The computer maps of the foot arch surface were obtained and the graphic reconstruction of the arch shape was performed in normal cases and in children with flatfoot. Most significant deviations of the foot arch shape, probably associated with the development delay, were detected in 4-5-year-old children under the dynamic load. Some additional advantages of holographic interferometry for the early diagnosis of flatfoot in children were demonstrated.

[The clinic skill in fixed appliance based on characteristics of Chinese normal occlusion].

PubMed

Bai, Ding; Luo, Song-jiao; Chen, Yang-xi; Xiao, Li-wei

2005-02-01

To study the bracket placement and arch wire bending based on ethnic differences and individual differences of normal occlusion. The prominence, tip, torque, upper first molar offset of crown and arch form between Chinese and Caucasian normal occlusion were compared. The results showed the ethnic differences of prominence, tip, torque, upper first molar offset of crown and arch form between Chinese and Caucasian normal occlusion. The placement of bracket was influenced by the crown morphology. The adjustments of the bracket placement and arch wire bending with Edgewise and pre-adjusted appliance are necessary to adapt to ethnic difference and individual difference.

Anomalous Origin of the Left Vertebral Artery from the Aortic Arch

PubMed Central

Einstein, Evan H.; Song, Linda H.; Villela, Natalia L. A.; Fasani-Feldberg, Gregory B.; Jacobs, Jonathan L.; Kim, Dolly O.; Nathawat, Akshay; Patel, Devika; Bender, Roger B.; Peters, Daniel F.

2016-01-01

Anatomic anomalies of the aortic arch have implications for clinical practice if their significance is understood. Our case study involves a cadaveric finding of the left vertebral artery originating directly from the aortic arch. Although this anatomical variation has been documented, the prevalence of this anomaly may be generally underestimated. After noting this anomaly, we analyzed 27 cases and found that four female cadavers had the left vertebral artery originating from the aortic arch rather than the left subclavian artery. With a prevalence rate of 14.8%, it would seem that this anomaly is more significant than previously thought, which could have implications for surgical practice. PMID:27757404

Anomalous Origin of the Left Vertebral Artery from the Aortic Arch.

PubMed

Einstein, Evan H; Song, Linda H; Villela, Natalia L A; Fasani-Feldberg, Gregory B; Jacobs, Jonathan L; Kim, Dolly O; Nathawat, Akshay; Patel, Devika; Bender, Roger B; Peters, Daniel F

2016-04-01

Anatomic anomalies of the aortic arch have implications for clinical practice if their significance is understood. Our case study involves a cadaveric finding of the left vertebral artery originating directly from the aortic arch. Although this anatomical variation has been documented, the prevalence of this anomaly may be generally underestimated. After noting this anomaly, we analyzed 27 cases and found that four female cadavers had the left vertebral artery originating from the aortic arch rather than the left subclavian artery. With a prevalence rate of 14.8%, it would seem that this anomaly is more significant than previously thought, which could have implications for surgical practice.

An Experimental Investigation on the Generation of a Stable Arch in Granular Materials Using a Developed Trapdoor Apparatus

NASA Astrophysics Data System (ADS)

Ahmadi, Ali; Seyedi Hosseininia, Ehsan

2017-06-01

This paper discusses the formation of stable arches in granular materials by using a series of laboratory tests. To this aim, a developed trapdoor apparatus is designed to find dimensions of arches formed over the door in cohesionless aggregates. This setup has two new important applications. In order to investigate the maximum width of the opening generated exactly on the verge of failure, the door can be open to an arbitrary size. In addition, the box containing granular materials (or base angle) is able to be set on optional angles from zero to 90 degrees with respect to the horizontal. Therefore, it is possible to understand the effect of different levels of gravity accelerations on the formed arches. It is observed that for all tested granular materials, increasing the door size and decreasing the base angle, both cause to increase the width and height of the arch. Moreover, the shape of all arches is governed by a parabola. Furthermore, the maximum door width is approximately five to 8.6 times the particle size, depending on the internal friction angle of materials and the base angle.

Effect of arch type and Body Mass Index on plantar pressure distribution during stance phase of gait.

PubMed

O'Brien, Davida Louise; Tyndyk, Magdalena

2014-01-01

Several factors have been associated with the presence of abnormally high plantar foot pressure including: (i) increased body weight, (ii) foot structure and (iii) walking strategy. It is predicted that the biomechanics of the foot is influenced by the structure of the foot, primarily the Medial Longitudinal Arch. The objective of this study was to examine if Body Mass Index and the foot arch have a direct effect on dynamic peak plantar pressure for healthy subjects. Following a clinical lower limb examination, the Tekscan HR mat was utilised for this study, plantar pressure was profiled at specific events during stance phase of gait including heel strike, midstance and toe off. Results indicated to the preferable normal arch as this produced a low plantar pressure distribution in all cases. The 2nd and 3rd metatarsal head region recorded the highest pressure for all arch types during dynamic analysis. The lowest pressure for the normal and overweight BMI was at toe-off. While the obese BMI group showed highest pressure during toe-off. The obese BMI flat arch subcategory indicated to functional ambulation differences. Future work involves comparing this healthy database to a demographically matched diabetic group.

Effects of Lower Third Molar Angulation and Position on Lower Arch Crowding.

PubMed

Selmani, Mimoza E; Gjorgova, Julijana; Selmani, Manushaqe E; Shkreta, Mirsad; Duci, Shkelzen B

2016-01-01

The role of the third molars in lower arch crowding has been debated for more than a century. The aim of this study was to determine the relationship between lower arch crowding and the presence of angulation and position of lower third molar. The measurements of the dental arch were made in 120 subjects aged 16 to 21 years, with average age to 18 years. The subjects were divided into two groups: Class I normal occlusion comprised 35 male and 25 female with mean age 18.87years, whereas Class I crowding comprised 27 males and 33 females with mean age 18.5 years. The dental pantomogram (DPT) were used to calculate the ratio of retromolar space (Ganss ratio), angulation of third molar to second molar and third molar to the base of the mandible. The results showed that measurements of Ganss ratio, third molar angulation to the base of the mandible, and third molar to second molar inclination, was statistically significant between crowded and normal groups. It can be concluded that there was a strong relationship between angulation and position of third molars and lower arch crowding. Key words: Third molars, angulation, lower arch, crowding

Monitoring of a concrete arch bridge during construction

NASA Astrophysics Data System (ADS)

Inaudi, Daniele; Ruefenacht, A.; von Arx, B.; Noher, H. P.; Vurpillot, Samuel; Glisic, Branko

2002-06-01

The Siggenthal Bridge is a concrete arch bridge with an arch span of 117 m, being built over the Limmat River in Baden, Switzerland. This bridge has been instrumented with 58 long- gage SOFO fiber optic deformation sensors, 2 inclinometers and 8 temperature sensors to monitor its deformations, curvatures and displacements during construction and int eh long-term. The sensor have been built installed successfully and the arch was monitored during the removal of the formwork and supports. It was therefore possible to observe the deformations of the arch wen being loaded by its dead load and by the daily temperature fluctuations. The measurements have shown that the temperature changes produce deformations of the same order of magnitude as the dead loads. The out-of-plain displacements obtained by double- integration of the measured curvatures are in good agreement with the direct triangulation measurements. Monitoring was also carried out during the construction of the superstructure, with the associated change of the load distribution in the arch. This paper briefly introduces the functional principle of the long-gage sensors used in this application, illustrates their installation and discusses the measurement results obtained during the bridge construction.

An eye movement analysis of the effect of interruption modality on primary task resumption.

PubMed

Ratwani, Raj; Trafton, J Gregory

2010-06-01

We examined the effect of interruption modality (visual or auditory) on primary task (visual) resumption to determine which modality was the least disruptive. Theories examining interruption modality have focused on specific periods of the interruption timeline. Preemption theory has focused on the switch from the primary task to the interrupting task. Multiple resource theory has focused on interrupting tasks that are to be performed concurrently with the primary task. Our focus was on examining how interruption modality influences task resumption.We leverage the memory-for-goals theory, which suggests that maintaining an associative link between environmental cues and the suspended primary task goal is important for resumption. Three interruption modality conditions were examined: auditory interruption with the primary task visible, auditory interruption with a blank screen occluding the primary task, and a visual interruption occluding the primary task. Reaction time and eye movement data were collected. The auditory condition with the primary task visible was the least disruptive. Eye movement data suggest that participants in this condition were actively maintaining an associative link between relevant environmental cues on the primary task interface and the suspended primary task goal during the interruption. These data suggest that maintaining cue association is the important factor for reducing the disruptiveness of interruptions, not interruption modality. Interruption-prone computing environments should be designed to allow for the user to have access to relevant primary task cues during an interruption to minimize disruptiveness.

Improving the effectiveness of an interruption lag by inducing a memory-based strategy.

PubMed

Morgan, Phillip L; Patrick, John; Tiley, Leyanne

2013-01-01

The memory for goals model (Altmann & Trafton, 2002) posits the importance of a short delay (the 'interruption lag') before an interrupting task to encode suspended goals for retrieval post-interruption. Two experiments used the theory of soft constraints (Gray, Simms, Fu & Schoelles, 2006) to investigate whether the efficacy of an interruption lag could be improved by increasing goal-state access cost to induce a more memory-based encoding strategy. Both experiments used a copying task with three access cost conditions (Low, Medium, and High) and a 5-s interruption lag with a no lag control condition. Experiment 1 found that the participants in the High access cost condition resumed more interrupted trials and executed more actions correctly from memory when coupled with an interruption lag. Experiment 2 used a prospective memory test post-interruption and an eyetracker recorded gaze activity during the interruption lag. The participants in the High access cost condition with an interruption lag were best at encoding target information during the interruption lag, evidenced by higher scores on the prospective memory measure and more gaze activity on the goal-state during the interruption lag. Theoretical and practical issues regarding the use of goal-state access cost and an interruption lag are discussed. Copyright © 2012. Published by Elsevier B.V.

Do interruptions affect quality of work?

PubMed

Foroughi, Cyrus K; Werner, Nicole E; Nelson, Erik T; Boehm-Davis, Deborah A

2014-11-01

The aim of this study was to determine if interruptions affect the quality of work. Interruptions are commonplace at home and in the office. Previous research in this area has traditionally involved time and errors as the primary measures of disruption. Little is known about the effect interruptions have on quality of work. Fifty-four students outlined and wrote three essays using a within-subjects design. During Condition 1, interruptions occurred while participants were outlining. During Condition 2, interruptions occurred while they were writing. No interruptions occurred in Condition 3. Quality of work was significantly reduced in both interruption conditions when compared to the non-interruption condition. The number of words produced was significantly reduced when participants were interrupted while writing the essay but not when outlining the essay. This research represents a crucial first step in understanding the effect interruptions have on quality of work. Our research suggests that interruptions negatively impact quality of work during a complex, creative writing task. Since interruptions are such a prevalent part of daily life, more research needs to be conducted to determine what other tasks are negatively impacted. Moreover, the underlying mechanism(s) causing these decrements needs to be identified. Finally, strategies and systems need to be designed and put in place to help counteract the decline in quality of work caused by interruptions.

A three-dimensional placoderm (stem-group gnathostome) pharyngeal skeleton and its implications for primitive gnathostome pharyngeal architecture.

PubMed

Brazeau, Martin D; Friedman, Matt; Jerve, Anna; Atwood, Robert C

2017-09-01

The pharyngeal skeleton is a key vertebrate anatomical system in debates on the origin of jaws and gnathostome (jawed vertebrate) feeding. Furthermore, it offers considerable potential as a source of phylogenetic data. Well-preserved examples of pharyngeal skeletons from stem-group gnathostomes remain poorly known. Here, we describe an articulated, nearly complete pharyngeal skeleton in an Early Devonian placoderm fish, Paraplesiobatis heinrichsi Broili, from Hunsrück Slate of Germany. Using synchrotron light tomography, we resolve and reconstruct the three-dimensional gill arch architecture of Paraplesiobatis and compare it with other gnathostomes. The preserved pharyngeal skeleton comprises elements of the hyoid arch (probable ceratohyal) and a series of branchial arches. Limited resolution in the tomography scan causes some uncertainty in interpreting the exact number of arches preserved. However, at least four branchial arches are present. The final and penultimate arches are connected as in osteichthyans. A single median basihyal is present as in chondrichthyans. No dorsal (epibranchial or pharyngobranchial) elements are observed. The structure of the pharyngeal skeleton of Paraplesiobatis agrees well with Pseudopetalichthys from the same deposit, allowing an alternative interpretation of the latter taxon. The phylogenetic significance of Paraplesiobatis is considered. A median basihyal is likely an ancestral gnathostome character, probably with some connection to both the hyoid and the first branchial arch pair. Unpaired basibranchial bones may be independently derived in chondrichthyans and osteichthyans. © 2017 The Authors Journal of Morphology Published by Wiley Periodicals, Inc.

Research on the reasonable pile spacing of micro pile composite soil nailing

NASA Astrophysics Data System (ADS)

Liu, Jun yan; Liu, Yan; Song, Xiang hua

2017-08-01

Through the numerical simulation software FLAC3D, study on the synergetic effect of micro pile composite soil nailing will be studied. By adjusting the micro pile spacing and analysing the displacement field and stress field of soil, we can find that supporting effect of the soil nail hasn’t work yet when the micro pile spacing is 2D. The soil arching between piles has been formed in the pile spacing 4D ∼ 6D. The composite effect of micro pile and soil nailing will be the best and the soil arch behind piles will be firstly formed in 6D, the horizontal saddle soil arch will be formed between the nails. The nail head coincidence pressure area and micro pile pressure area are overlapping to maintain stability in the soil between piles. When the micro pile spacing is 9D, the arch behind piles will be failure, the soil flows around, but the saddle arch between the nails into circular arch, the supporting effect of the soil nailing is enhanced. When the micro pile spacing is 12D, the arch of the nails becomes smaller, sliding surface appears primitively. Based on the conclusions above, it is suggested that the micro pile spacing between 2D ∼ 6D is suitable for the micro pile and soil nailing composite support. The conclusion can provide theoretical basis for the design and construction of micro pile composite soil nailing.

Optical Silencing of C. elegans Cells with Arch Proton Pump

PubMed Central

Okazaki, Ayako; Sudo, Yuki; Takagi, Shin

2012-01-01

Background Optogenetic techniques using light-driven ion channels or ion pumps for controlling excitable cells have greatly facilitated the investigation of nervous systems in vivo. A model organism, C. elegans, with its small transparent body and well-characterized neural circuits, is especially suitable for optogenetic analyses. Methodology/Principal Findings We describe the application of archaerhodopsin-3 (Arch), a recently reported optical neuronal silencer, to C. elegans. Arch::GFP expressed either in all neurons or body wall muscles of the entire body by means of transgenes were localized, at least partially, to the cell membrane without adverse effects, and caused locomotory paralysis of worms when illuminated by green light (550 nm). Pan-neuronal expression of Arch endowed worms with quick and sustained responsiveness to such light. Worms reliably responded to repeated periods of illumination and non-illumination, and remained paralyzed under continuous illumination for 30 seconds. Worms expressing Arch in different subsets of motor neurons exhibited distinct defects in the locomotory behavior under green light: selective silencing of A-type motor neurons affected backward movement while silencing of B-type motor neurons affected forward movement more severely. Our experiments using a heat-shock-mediated induction system also indicate that Arch becomes fully functional only 12 hours after induction and remains functional for more than 24 hour. Conclusions/Sgnificance Arch can be used for silencing neurons and muscles, and may be a useful alternative to currently widely used halorhodopsin (NpHR) in optogenetic studies of C. elegans. PMID:22629299

Maxillary arch width and buccal corridor changes with orthodontic treatment. Part 1: differences between premolar extraction and nonextraction treatment outcomes.

PubMed

Meyer, Anna H; Woods, Michael G; Manton, David J

2014-02-01

In this retrospective study, we examined and compared the pretreatment and posttreatment arch widths and buccal corridor changes in subjects who had received orthodontic treatment either with or without premolar extractions. Pretreatment and posttreatment casts, frontal smiling photographs, and lateral cephalograms of 30 extraction and 27 nonextraction patients were analyzed to determine any significant differences in arch widths, buccopalatal inclinations of the teeth, and buccal corridor widths and areas, both within and between the 2 groups. Relationships between buccal corridor measurements and corresponding arch widths and buccopalatal inclinations of the teeth were also examined. There was a significant increase in the posttreatment maxillary intercanine width in the extraction group but not in the nonextraction group. Both the pretreatment and posttreatment arch widths between the maxillary first molars and at the level of the posterior rugae were greater in the nonextraction group than in the extraction group. There were no significant differences in any buccal corridor widths or areas measured between the extraction and nonextraction subjects. Because they reflect different morphologies, there are likely to be significant differences in average maxillary anterior and posterior posttreatment arch widths in those treated with or without extractions. However, these arch width differences are not likely to be discernible in extraction and nonextraction patients as differences in the buccal corridor widths and areas. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Investigating Interruptions: Implications for Flightdeck Performance

NASA Technical Reports Server (NTRS)

Latorella, Kara A.

1999-01-01

A fundamental aspect of multiple task management is attending to new stimuli and integrating associated task requirements into an ongoing task set; this is "interruption management" (IM). Anecdotal evidence and field studies indicate the frequency and consequences of interruptions, however experimental investigations of mechanisms influencing IM are scarce. Interruptions on commercial flightdecks are numerous, of various forms, and have been cited as contributing factors in many aviation incident and accident reports. This research grounds an experimental investigation of flightdeck interruptions in a proposed IM stage model. This model organizes basic research, identifies influencing mechanisms, and suggests appropriate dependent measures for IM. Fourteen airline pilots participated in a flightdeck simulation experiment to investigate the general effects of performing an interrupting task and interrupted procedure, and the effects of specific task factors: (1) modality; (2) embeddedness, or goal-level, of an interruption; (3) strength of association, or coupling-strength, between interrupted tasks; (4) semantic similarity; and (5) environmental stress. General effects of interruptions were extremely robust. All individual task factors significantly affected interruption management, except "similarity." Results extend the Interruption Management model, and are interpreted for their implications for interrupted flightdeck performance and intervention strategies for mitigating their effects on the flightdeck.

The role of cardiovascular magnetic resonance in the assessment of severe aortic stenosis and in post-procedural evaluation following transcatheter aortic valve implantation and surgical aortic valve replacement.

PubMed

Musa, Tarique Al; Plein, Sven; Greenwood, John P

2016-06-01

Degenerative aortic stenosis (AS) is the most common valvular disease in the western world with a prevalence expected to double within the next 50 years. International guidelines advocate the use of cardiovascular magnetic resonance (CMR) as an investigative tool, both to guide diagnosis and to direct optimal treatment. CMR is the reference standard for quantifying both left and right ventricular volumes and mass, which is essential to assess the impact of AS upon global cardiac function. Given the ability to image any structure in any plane, CMR offers many other diagnostic strengths including full visualisation of valvular morphology, direct planimetry of orifice area, the quantification of stenotic jets and in particular, accurate quantification of valvular regurgitation. In addition, CMR permits reliable and accurate measurements of the aortic root and arch which can be fundamental to appropriate patient management. There is a growing evidence base to indicate tissue characterisation using CMR provides prognostic information, both in asymptomatic AS patients and those undergoing intervention. Furthermore, a number of current clinical trials will likely raise the importance of CMR in routine patient management. This article will focus on the incremental value of CMR in the assessment of severe AS and the insights it offers following valve replacement.

Aortic Dissection in Turner Syndrome

PubMed Central

Bondy, Carolyn A.

2009-01-01

Purpose of review Turner syndrome (TS) is a relatively common disorder of female development with cardinal features of short stature and congenital cardiovascular defects (CHD). TS is the most common established cause of aortic dissection in young women, but has received little attention outside of pediatric literature. This review focuses on emerging knowledge of the characteristics of aortic disease in TS in comparison with Marfan-like syndromes and isolated aortic valve disease. Recent findings The incidence of aortic dissection is significantly increased in individuals with TS at all ages, highest during young adult years and in pregnancy. Pediatric patients with dissection have known CHD, but adults often have aortic valve and arch abnormalities detected only by screening cardiac MR (CMR). Thoracic aortic dilation in TS must be evaluated in relation to body surface area (BSA). Dilation is most prominent at the ascending aorta similar to the pattern seen in non-syndromic bicuspid aortic valve (BAV), is equally prevalent (20-30%) in children and adults, and does not seem to be rapidly progressive. Cardiovascular anomalies and risk for aortic dissection in TS are strongly linked to a history of fetal lymphedema, evidenced by the presence of neck webbing and shield chest. Summary Risk for acute aortic dissection is increased by more than 100-fold in young and middle-aged women with TS. Monitoring frequency and treatment modalities are decided on an individual basis until more information on outcomes becomes available. PMID:18839441

Progressive Care Nurses Improving Patient Safety by Limiting Interruptions During Medication Administration.

PubMed

Flynn, Fran; Evanish, Julie Q; Fernald, Josephine M; Hutchinson, Dawn E; Lefaiver, Cheryl

2016-08-01

Because of the high frequency of interruptions during medication administration, the effectiveness of strategies to limit interruptions during medication administration has been evaluated in numerous quality improvement initiatives in an effort to reduce medication administration errors. To evaluate the effectiveness of evidence-based strategies to limit interruptions during scheduled, peak medication administration times in 3 progressive cardiac care units (PCCUs). A secondary aim of the project was to evaluate the impact of limiting interruptions on medication errors. The percentages of interruptions and medication errors before and after implementation of evidence-based strategies to limit interruptions were measured by using direct observations of nurses on 2 PCCUs. Nurses in a third PCCU served as a comparison group. Interruptions (P < .001) and medication errors (P = .02) decreased significantly in 1 PCCU after implementation of evidence-based strategies to limit interruptions. Avoidable interruptions decreased 83% in PCCU1 and 53% in PCCU2 after implementation of the evidence-based strategies. Implementation of evidence-based strategies to limit interruptions in PCCUs decreases avoidable interruptions and promotes patient safety. ©2016 American Association of Critical-Care Nurses.

Cost of skid roads for arch logging in West Virginia

Treesearch

George R., Jr. Trimble; Carl R. Barr

1960-01-01

In the mountain hardwood country of the northern Appalachians, tree-length skidding with tractor and arch has proved to be economical logging. One essential part of this type of logging is that tree-length logs are winched to the skid roads: tractor and arch do not run around through the woods. Winching distance is commonly 200 to 300 feet; and occasionally an extra...

10. COPY OF OBLIQUE PHOTOGRAPH SHOWING ARCH HANGAR AT RIGHT, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. COPY OF OBLIQUE PHOTOGRAPH SHOWING ARCH HANGAR AT RIGHT, BUILDING 8200 (OBSERVATION TOWER) AT LEFT, AND B-52 AIRCRAFT PARKED ALONG APRON IN BACKGROUND, DATED OCTOBER 1967, PHOTOGRAPH FROM BASE MASTER PLAN LOCATED AT AIR FORCE BASE CONVERSION AGENCY, LORING AIR FORCE BASE, MAINE. - Loring Air Force Base, Arch Hangar, East of Arizona Road near southern end of runway, Limestone, Aroostook County, ME

Stability of an arch type shock absorber made of a rubber-like material

NASA Astrophysics Data System (ADS)

Kabrits, Sergey A.; Kolpak, Eugeny P.

2018-05-01

The paper considers the stability problem of an arch shock absorber made of a rubber-like material. As a model, the nonlinear theory of thin shells from elastomers K.F. Chernykh is used. The case of symmetrical and asymmetrical deformation of an arch shock absorber under symmetrical compression is investigated. The possibility of asymmetric bifurcation is evaluated depending on the boundary conditions.

Nonlinear modes of snap-through motions of a shallow arch

NASA Astrophysics Data System (ADS)

Breslavsky, I.; Avramov, K. V.; Mikhlin, Yu.; Kochurov, R.

2008-03-01

Nonlinear modes of snap-through motions of a shallow arch are analyzed. Dynamics of shallow arch is modeled by a two-degree-of-freedom system. Two nonlinear modes of this discrete system are treated. The methods of Ince algebraization and Hill determinants are used to study stability of nonlinear modes. The analytical results are compared with the data of the numerical simulations.

Agreement in the determination of preformed wire shape templates on plaster models and customized digital arch form diagrams on digital models.

PubMed

Camardella, Leonardo Tavares; Sá, Maiara da Silva Bezerra; Guimarães, Luciana Campos; Vilella, Beatriz de Souza; Vilella, Oswaldo de Vasconcellos

2018-03-01

The aim of this study was to verify the accuracy of preformed wire shape templates on plaster models and those of customized digital arch form diagrams on digital models. Twenty pairs of dental plaster models were randomly selected from the archives of the Department of Orthodontics of Federal Fluminense University, Niterói, Rio de Janeiro, Brazil. All plaster model samples were scanned in a plaster model scanner to create the respective digital models. Three examiners defined the arch form on the mandibular arch of these models by selecting the ideal preformed wire shape template on each plaster model or by making a customized digital arch form on the digital models using a digital arch form customization tool. These 2 arch forms were superimposed by the best-fit method. The greatest differences in the 6 regions on the superimposed arches were evaluated. Each examiner presented a descriptive analysis with the means, standard deviation, and minimum and maximum intervals of the differences on the superimpositions. Intraclass correlation coefficient and paired t tests were used to evaluate the accuracy of the superimpositions. Among the 6 regions analyzed in the superimpositions, the largest differences in the anterior and premolar regions were considered clinically insignificant, whereas the largest differences in the right molar region, especially the second molar area, were considered clinically significant by all 3 examiners. The intraclass correlation coefficients showed a weak correlation in the premolar region and moderate correlations in the anterior and molar regions. The paired t test showed statistically significant differences in the left anterior and premolar regions. The superimpositions between the arch forms on plaster and digital models were considered accurate, and the differences were not clinically significant, with the exception of the second molar area. Despite the favorable results, the requirement of correcting some software problems may hamper the transition from plaster to digital models. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Classification of the height and flexibility of the medial longitudinal arch of the foot.

PubMed

Nilsson, Mette Kjærgaard; Friis, Rikke; Michaelsen, Maria Skjoldahl; Jakobsen, Patrick Abildgaard; Nielsen, Rasmus Oestergaard

2012-02-17

The risk of developing injuries during standing work may vary between persons with different foot types. High arched and low arched feet, as well as rigid and flexible feet, are considered to have different injury profiles, while those with normal arches may sustain fewer injuries. However, the cut-off values for maximum values (subtalar position during weight-bearing) and range of motion (ROM) values (difference between subtalar neutral and subtalar resting position in a weight-bearing condition) for the medial longitudinal arch (MLA) are largely unknown. The purpose of this study was to identify cut-off values for maximum values and ROM of the MLA of the foot during static tests and to identify factors influencing foot posture. The participants consisted of 254 volunteers from Central and Northern Denmark (198 m/56 f; age 39.0 ± 11.7 years; BMI 27.3 ± 4.7 kg/m2). Navicular height (NH), longitudinal arch angle (LAA) and Feiss line (FL) were measured for either the left or the right foot in a subtalar neutral position and subtalar resting position. Maximum values and ROM were calculated for each test. The 95% and 68% prediction intervals were used as cut-off limits. Multiple regression analysis was used to detect influencing factors on foot posture. The 68% cut-off values for maximum MLA values and MLA ROM for NH were 3.6 to 5.5 cm and 0.6 to 1.8 cm, respectively, without taking into account the influence of other variables. Normal maximum LAA values were between 131 and 152° and normal LAA ROM was between -1 and 13°. Normal maximum FL values were between -2.6 and -1.2 cm and normal FL ROM was between -0.1 and 0.9 cm. Results from the multivariate linear regression revealed an association between foot size with FL, LAA, and navicular drop. The cut-off values presented in this study can be used to categorize people performing standing work into groups of different foot arch types. The results of this study are important for investigating a possible link between arch height and arch movement and the development of injuries.

[Shunt and short circuit].

PubMed

Rangel-Abundis, Alberto

2006-01-01

Shunt and short circuit are antonyms. In French, the term shunt has been adopted to denote the alternative pathway of blood flow. However, in French, as well as in Spanish, the word short circuit (court-circuit and cortocircuito) is synonymous with shunt, giving rise to a linguistic and scientific inconsistency. Scientific because shunt and short circuit made reference to a phenomenon that occurs in the field of the physics. Because shunt and short circuit are antonyms, it is necessary to clarify that shunt is an alternative pathway of flow from a net of high resistance to a net of low resistance, maintaining the stream. Short circuit is the interruption of the flow, because a high resistance impeaches the flood. This concept is applied to electrical and cardiovascular physiology, as well as to the metabolic pathways.

Occlusal plane location in edentulous patients: a review.

PubMed

Shetty, Sanath; Zargar, Nazia Majeed; Shenoy, Kamalakanth; Rekha, V

2013-09-01

Occlusal plane orientation is an important factor in the construction of a complete denture. Occlusal plane could be oriented using landmarks in the mandibular arch as well as in the maxillary arch. In the mandibular arch there are few landmarks which could be used to orient the occlusal plane like the retromolar pad, corner of the lips (lower lip length) whereas the maxillary arch has a number of landmarks, of which the ala-tragal line is the most commonly used and the same being the most controversial. In the following article different landmarks and its accuracy for orientating the occlusal plane in an edentulous subject as studied by various authors has been discussed.

Performance of 75 millimeter-bore arched outer-race ball bearings

NASA Technical Reports Server (NTRS)

Coe, H. H.; Hamrock, B. J.

1976-01-01

An investigation was performed to determine the operating characteristics of 75-mm bore, arched outer-race bearings, and to compare the data with those for a similar, but conventional, deep groove ball bearing. Further, results of an analytical study, made using a computer program developed previously, were compared with the experimental data. Bearings were tested up to 28,000 rpm shaft speed with a load of 2200 N (500 lb). The amount of arching was 0.13, 0.25, and 0.51 mm (.005, .010, and .020 in.). All bearings operated satisfactorily. The outer-race temperatures and the torques, however, were consistently higher for the arched bearings than for the conventional bearing.

Modified lateral orbitotomy for removal of orbital neoplasms in two dogs.

PubMed

Gilger, B C; Whitley, R D; McLaughlin, S A

1994-01-01

A simplified lateral orbitotomy is described that decreases surgical time and lessens tissue dissection, yet maintains the exposure to the orbit provided by other orbitotomy techniques. The approach involves cutting the orbital ligament, incising the temporalis aponeurosis from the dorsal zygomatic arch, making parallel zygomatic arch osteotomies, and reflecting the zygomatic arch ventrally. Closure of the wound involves wiring the zygomatic arch back into place. This orbitotomy procedure provides excellent exposure for removal or biopsy of orbital masses. The use of this technique for surgical excision of orbital masses in two dogs, one with an adenoma of the third eyelid gland and one with an orbital fibrosarcoma, and their subsequent management is described.

Performance of 75-millimeter bore arched outer-race ball bearings

NASA Technical Reports Server (NTRS)

Coe, H. H.; Hamrock, B. J.

1976-01-01

An investigation was performed to determine the operating characteristics of 75-mm bore, arched outer-race bearings, and to compare the data with those for a similar, but conventional, deep groove ball bearing. Further, results of an analytical study, made using a computer program developed previously, were compared with the experimental data. Bearings were tested up to 28,000 rpm shaft speed with a load of 2,200 N (500 lb). The amount of arching was 0.13, 0.25, and 0.51 mm (0.005, 0.010, and 0.020 in). All bearings operated satisfactorily. The outer-race temperatures and the torques, however, were consistently higher for the arched bearings than for the conventional bearings

The time-course of recovery from interruption during reading: eye movement evidence for the role of interruption lag and spatial memory.

PubMed

Cane, James E; Cauchard, Fabrice; Weger, Ulrich W

2012-01-01

Two experiments examined how interruptions impact reading and how interruption lags and the reader's spatial memory affect the recovery from such interruptions. Participants read paragraphs of text and were interrupted unpredictably by a spoken news story while their eye movements were monitored. Time made available for consolidation prior to responding to the interruption did not aid reading resumption. However, providing readers with a visual cue that indicated the interruption location did aid task resumption substantially in Experiment 2. Taken together, the findings show that the recovery from interruptions during reading draws on spatial memory resources and can be aided by processes that support spatial memory. Practical implications are discussed.

The Ponta Grossa Arch: A proposal for ts configuration and evolution from the interpretation of remote sensing data. M.S. Thesis

NASA Technical Reports Server (NTRS)

Parada, N. D. J. (Principal Investigator); Dealmeida, T. I. R.

1983-01-01

Visual analysis of MSS imagery was used to construct a map of dikes in a wide area of the Ponta Grossa Arch both in the Parana Basin and its basement. Analysis of the map by photographic methods defined the zone of highest density of the dikes, and some aspects of the longitudinal and transverse heterogeneities, as well as localized the apex of the Arch. Borders of the Arch were also suggested. Field investigations confirmed the position of the apex of the flexure on Palezoic sediments and pre-lava Mesozoic sediments. Controversial aspects of the relative absence of dikes in certain units or lithologies and the composition of intrusions surrounding the city of Castro were observed. The apparent synchronism between the activity of the Parana Basin and the Arch is discussed as well as the frequent inverse characteristics of vertical movements. The similarity of rocks in Brazil and Africa is also considered.

The growth of filaments by the condensation of coronal arches

NASA Technical Reports Server (NTRS)

Davis, J. M.; Krieger, A. S.

1982-01-01

A model of filament formation based on the condensation of coronal arches is described. The condensation results from initiating the radiative instability within an arch by superimposing a transient energy supply upon the steady state heating mechanism. The transient energy supply increases the density within the arch so that when it is removed the radiative losses are sufficient to lead to cooling below the minimum in the power loss curve. Times from the initial formation of the condensation to its temperature stabilization as a cool filament have been calculated for various initial conditions. They lie in the range 10,000-100,000 s with the majority of the time spent above a temperature of 1 x 10 to the 6th K. Under the assumption that the condensation of a single arch forms an element of the filament, a complete filament requires the condensation of an arcade of loops. Using experimentally derived parameters, filament densities of 10 to the 11th to 10 to the 12th per cu cm can be obtained.

2. View looking Northeast. The masonry section of the viaduct, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. View looking Northeast. The masonry section of the viaduct, west of the river, was 1,382 feet long and consisted of eight segmental arches of 83 foot span and two segmental arches of 97.5 foot span plus intervening sections of retaining wall. Eight of the Masonry arches, made of Berea Sandstone, still stand - Superior Avenue Viaduct, Cleveland East & West side, Cuyahoga Valley Vicinity, Cleveland, Cuyahoga County, OH

Parascapular mass revealing primary tuberculosis of the posterior arch

PubMed Central

Arbault, Anais; Ornetti, Paul; Chevallier, Olivier; Avril, Julien; Pottecher, Pierre

2016-01-01

We report the case of a parascapular abscess revealing primary tuberculosis of the posterior arch in a 31-year-old man. Sectional imaging is essential in order to detect the different lesions of this atypical spinal tuberculosis as osteolysis of the posterior arch extendible to vertebral body, osteocondensation, epidural extension which is common in this location, and high specificity of a zygapophysial, costo-vertebral or transverse arthritis. PMID:27709081

Fuel cell current collector

DOEpatents

Katz, Murray; Bonk, Stanley P.; Maricle, Donald L.; Abrams, Martin

1991-01-01

A fuel cell has a current collector plate (22) located between an electrode (20) and a separate plate (25). The collector plate has a plurality of arches (26, 28) deformed from a single flat plate in a checkerboard pattern. The arches are of sufficient height (30) to provide sufficient reactant flow area. Each arch is formed with sufficient stiffness to accept compressive load and sufficient resiliently to distribute the load and maintain electrical contact.

Cooperative action of multiple cis-acting elements is required for N-myc expression in branchial arches: specific contribution of GATA3.

PubMed

Potvin, Eric; Beuret, Laurent; Cadrin-Girard, Jean-François; Carter, Marcelle; Roy, Sophie; Tremblay, Michel; Charron, Jean

2010-11-01

The precise expression of the N-myc proto-oncogene is essential for normal mammalian development, whereas altered N-myc gene regulation is known to be a determinant factor in tumor formation. Using transgenic mouse embryos, we show that N-myc sequences from kb -8.7 to kb +7.2 are sufficient to reproduce the N-myc embryonic expression profile in developing branchial arches and limb buds. These sequences encompass several regulatory elements dispersed throughout the N-myc locus, including an upstream limb bud enhancer, a downstream somite enhancer, a branchial arch enhancer in the second intron, and a negative regulatory element in the first intron. N-myc expression in the limb buds is under the dominant control of the limb bud enhancer. The expression in the branchial arches necessitates the interplay of three regulatory domains. The branchial arch enhancer cooperates with the somite enhancer region to prevent an inhibitory activity contained in the first intron. The characterization of the branchial arch enhancer has revealed a specific role of the transcription factor GATA3 in the regulation of N-myc expression. Together, these data demonstrate that correct N-myc developmental expression is achieved via cooperation of multiple positive and negative regulatory elements.

Loss of unc45a precipitates arteriovenous shunting in the aortic arches

PubMed Central

Anderson, Matthew J.; Pham, Van N.; Vogel, Andreas M.; Weinstein, Brant M.; Roman, Beth L.

2008-01-01

Aortic arch malformations are common congenital disorders that are frequently of unknown etiology. To gain insight into the factors that guide branchial aortic arch development, we examined the process by which these vessels assemble in wild type zebrafish embryos and in kurzschlusstr12 (kus tr12) mutants. In wild type embryos, each branchial aortic arch first appears as an island of angioblasts in the lateral pharyngeal mesoderm, then elaborates by angiogenesis to connect to the lateral dorsal aorta and ventral aorta. In kustr12 mutants, angioblast formation and initial sprouting are normal, but aortic arches 5 and 6 fail to form a lumenized connection to the lateral dorsal aorta. Blood enters these blind-ending vessels from the ventral aorta, distending the arteries and precipitating fusion with an adjacent vein. This arteriovenous malformation (AVM), which shunts nearly all blood directly back to the heart, is not genetically programmed, as its formation correlates with blood flow and aortic arch enlargement. By positional cloning, we have identified a nonsense mutation in unc45a in kustr12 mutants. Our results are the first to ascribe a role for Unc45a, a putative myosin chaperone, in vertebrate development, and identify a novel mechanism by which an AVM can form. PMID:18462713

An investigation of the seismic behavior of a deck-type reinforced concrete arch bridge

NASA Astrophysics Data System (ADS)

Farahani, Emadoddin Majdabadi; Maalek, Shahrokh

2017-07-01

This paper attempts to explore potential benefits of form in a deck-type reinforced concrete (RC) arch bridge in connection with its overall seismic behavior and performance. Through a detailed three-dimensional finite element modeling and analysis of an actual existing deck-type RC arch bridge, some useful quantitative information have been derived that may serve for a better understanding of the seismic behavior of such arch bridges. A series of the nonlinear dynamic analyses has been carried out under the action of seven different time histories of ground motion scaled to the AASHTO 2012 response spectrum. The concept of demand to capacity ratios has been employed to provide an initial estimation of the seismic performance of the bridge members. As a consequence of the structural form, a particular type of irregularity is introduced due to variable heights of columns transferring the deck loads to the main arch. Hence, a particular attention has been paid to the internal force/moment distributions within the short, medium, and long columns as well as along the main arch. A study of the effects of the vertical component of ground motion has demonstrated the need for the inclusion of these effects in the analysis of such bridges.

Evaluation of the relationship between the static measurement of transverse arch flexibility of the forefoot and gait parameters in healthy subjects.

PubMed

Kondo, Takashi; Muneta, Takeshi; Fukui, Tsutomu

2017-03-01

[Purpose] To investigate the relationship between the static measurement of the transverse arch of the forefoot, using a 3-dimensional (3D) foot scanner, and kinetics and kinematics of gait parameters in the sagittal plane. [Subjects and Methods] Twenty healthy subjects participated in this study. The transverse arch of the forefoot was measured under three conditions as follows: condition 1, sitting; condition 2, standing; and condition 3, foot forward and lower leg tilting anteriorly to the maximum position with heel contact. Gait parameters were recorded using a 3D motion analysis system and force plate. Correlation coefficients between TAF for each comparison of conditions and gait parameters were calculated using the Spearman correlation analysis. [Results] Rates of the transverse arch of the forefoot width and height between condition 2 and condition 3 were significantly correlated with the anterior and posterior component of ground reaction forces, the hip joint extension angle, and the ankle plantar flexion moment. [Conclusion] Our study's findings indicated that increased stiffness of the transverse arch of the forefoot was related to the increase in ankle plantar moment, and decreased stiffness of the transverse arch of the forefoot was related to the increase in hip joint extension angle during gait.

Rearfoot alignment and medial longitudinal arch configurations of runners with symptoms and histories of plantar fasciitis

PubMed Central

Ribeiro, Ana Paula; Trombini-Souza, Francis; Tessutti, Vitor; Lima, Fernanda Rodrigues; de Camargo Neves Sacco, Isabel; João, Sílvia Maria Amado

2011-01-01

OBJECTIVE: To evaluate and compare rearfoot alignment and medial longitudinal arch index during static postures in runners, with and without symptoms and histories of plantar fasciitis (PF). INTRODUCTION: PF is the third most common injury in runners but, so far, its etiology remains unclear. In the literature, rearfoot misalignment and conformations of the longitudinal plantar arch have been described as risk factors for the development of PF. However, in most of the investigated literature, the results are still controversial, mainly regarding athletic individuals and the effects of pain associated with these injuries. METHODS: Forty-five runners with plantar fasciitis (30 symptomatic and 15 with previous histories of injuries) and 60 controls were evaluated. Pain was assessed by a visual analogue scale. The assessment of rearfoot alignment and the calculations of the arch index were performed by digital photographic images. RESULTS: There were observed similarities between the three groups regarding the misalignments of the rearfoot valgus. The medial longitudinal arches were more elevated in the group with symptoms and histories of PF, compared to the control runners. CONCLUSIONS: Runners with symptoms or histories of PF did not differ in rearfoot valgus misalignments, but showed increases in the longitudinal plantar arch during bipedal static stance, regardless of the presence of pain symptoms. PMID:21808870

Orthodontic Intervention to Impacted and Transposed Lower Canines

PubMed Central

Kılıç, Nihat

2017-01-01

Impacted and transposed teeth cause serious difficulties in tooth eruption and movement as well as esthetic and functional outcomes. Proper treatment planning including good biomechanical control is essential in order to avoid side effects during traction and aligning of the impacted and/or transposed teeth. The purpose of the present study was to present a successfully treated female patient having transposed and impacted lower canines by means of a modified lingual arch and fixed orthodontic appliance. A female patient aged 13 years and 9 months presented to the orthodontic department with a chief compliant of bilateral spacing and missing teeth in mandibular dentition. After leveling and creating sufficient space in the mandibular arch for the canines, a modified lingual arch was cemented to the mandibular first molars. The lingual arch had two hooks extending to the distobuccal areas of the canine spaces. Elastic chains were applied between the hooks on the lingual arch and the ligatures tied to the attachments on the canine crowns. The light forces generated by elastic materials caused impacted canines to erupt and tend towards their own spaces in the dental arch. As a result, impacted and transposed lower canines were properly positioned in their spaces, and the treatment results were stable during the retention period. PMID:28540090

Role of the tranverse arch in stiffness of the human foot

NASA Astrophysics Data System (ADS)

Dias, Marcelo A.; Singh, Dhiraj K.; Bandi, Mahesh M.; Venkadesan, Madhusudhan; Mandre, Shreyas

2015-03-01

Human ancestors evolved from walking, around 6 million years (Ma) ago, to regular endurance running, around 2 Ma ago. Simultaneously, the feet evolved from a relatively flat structure like that of current day Chimpanzees (or our hands), to the modern human foot with two arches, a longitudinal and a transversal arch. The feet play a crucial role in locomotion by providing sufficient stiffness for propulsion, and being soft and pliable to absorb impacts and store energy elastically. Here we show that the transverse arch could play a central role in stiffness modulation. We first treat the foot as an elastic shell that is with intrinsic curvature. Calculations, numerics and physical experiments all show that for a foot-like shell, the stiffness has a power-law dependence on transverse curvature beyond a critical value. On the other hand, for purely longitudinally curved feet, or transverse curvature below the critical value, lead to low stiffness like a flat plate. Discrete realizations of a continuum shell, more closely resembling the human foot, also exhibit curvature induced stiffening. These results shed light on the role of the quintessentially human feature of a doubly arched foot, and suggest mechanical consequences of disorders such as a collapsed arch. HFSP RGY0091/2013.

Evaluation of the relationship between the static measurement of transverse arch flexibility of the forefoot and gait parameters in healthy subjects

PubMed Central

Kondo, Takashi; Muneta, Takeshi; Fukui, Tsutomu

2017-01-01

[Purpose] To investigate the relationship between the static measurement of the transverse arch of the forefoot, using a 3-dimensional (3D) foot scanner, and kinetics and kinematics of gait parameters in the sagittal plane. [Subjects and Methods] Twenty healthy subjects participated in this study. The transverse arch of the forefoot was measured under three conditions as follows: condition 1, sitting; condition 2, standing; and condition 3, foot forward and lower leg tilting anteriorly to the maximum position with heel contact. Gait parameters were recorded using a 3D motion analysis system and force plate. Correlation coefficients between TAF for each comparison of conditions and gait parameters were calculated using the Spearman correlation analysis. [Results] Rates of the transverse arch of the forefoot width and height between condition 2 and condition 3 were significantly correlated with the anterior and posterior component of ground reaction forces, the hip joint extension angle, and the ankle plantar flexion moment. [Conclusion] Our study’s findings indicated that increased stiffness of the transverse arch of the forefoot was related to the increase in ankle plantar moment, and decreased stiffness of the transverse arch of the forefoot was related to the increase in hip joint extension angle during gait. PMID:28356622

A numerical procedure for failure mode detection of masonry arches reinforced with fiber reinforced polymeric materials

NASA Astrophysics Data System (ADS)

Galassi, S.

2018-05-01

In this paper a mechanical model of masonry arches strengthened with fibre-reinforced composite materials and the relevant numerical procedure for the analysis are proposed. The arch is modelled by using an assemblage of rigid blocks that are connected together and, also to the supporting structures, by mortar joints. The presence of the reinforcement, usually a sheet placed at the intrados or the extrados, prevents the occurrence of cracks that could activate possible collapse mechanisms, due to tensile failure of the mortar joints. Therefore, in a reinforced arch failure generally occurs in a different way from the URM arch. The numerical procedure proposed checks, as a function of an external incremental load, the inner stress state in the arch, in the reinforcement and in the adhesive layer. In so doing, it then provides a prediction of failure modes. Results obtained from experimental tests, carried out on four in-scale models performed in a laboratory, have been compared with those provided by the numerical procedure, implemented in ArchiVAULT, a software developed by the author. In this regard, the numerical procedure is an extension of previous works. Although additional experimental investigations are necessary, these former results confirm that the proposed numerical procedure is promising.

Interruption as a test of the user-computer interface

NASA Technical Reports Server (NTRS)

Kreifeldt, J. G.; Mccarthy, M. E.

1981-01-01

In order to study the effects different logic systems might have on interrupted operation, an algebraic calculator and a reverse polish notation calculator were compared when trained users were interrupted during problem entry. The RPN calculator showed markedly superior resistance to interruption effects compared to the AN calculator although no significant differences were found when the users were not interrupted. Causes and possible remedies for interruption effects are speculated. It is proposed that because interruption is such a common occurrence, it be incorporated into comparative evaluation tests of different logic system and control/display system and that interruption resistance be adopted as a specific design criteria for such design.

Role of cranial neural crest cells in visceral arch muscle positioning and morphogenesis in the Mexican axolotl, Ambystoma mexicanum.

PubMed

Ericsson, Rolf; Cerny, Robert; Falck, Pierre; Olsson, Lennart

2004-10-01

The role of cranial neural crest cells in the formation of visceral arch musculature was investigated in the Mexican axolotl, Ambystoma mexicanum. DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine, perchlorate) labeling and green fluorescent protein (GFP) mRNA injections combined with unilateral transplantations of neural folds showed that neural crest cells contribute to the connective tissues but not the myofibers of developing visceral arch muscles in the mandibular, hyoid, and branchial arches. Extirpations of individual cranial neural crest streams demonstrated that neural crest cells are necessary for correct morphogenesis of visceral arch muscles. These do, however, initially develop in their proper positions also in the absence of cranial neural crest. Visceral arch muscles forming in the absence of neural crest cells start to differentiate at their origins but fail to extend toward their insertions and may have a frayed appearance. Our data indicate that visceral arch muscle positioning is controlled by factors that do not have a neural crest origin. We suggest that the cranial neural crest-derived connective tissues provide directional guidance important for the proper extension of the cranial muscles and the subsequent attachment to the insertion on the correct cartilage. In a comparative context, our data from the Mexican axolotl support the view that the cranial neural crest plays a fundamental role in the development of not only the skeleton of the vertebrate head but also in the morphogenesis of the cranial muscles and that this might be a primitive feature of cranial development in vertebrates. 2004 Wiley-Liss, Inc.

Effects of pre-surgical nasoalveolar moulding on maxillary arch and nasal form in unilateral cleft lip and palate before lip surgery.

PubMed

Fuchigami, T; Kimura, N; Kibe, T; Tezuka, M; Amir, M S; Suga, H; Takemoto, Y; Hashiguchi, M; Maeda-Iino, A; Nakamura, N

2017-11-01

To investigate the effects of pre-surgical nasoalveolar moulding (PNAM) on the maxillary arch and nasal form in patients with unilateral cleft lip and palate (UCLP). This is a retrospective case series study. The subjects were infants with complete UCLP who were treated with PNAM (n = 18) at Kagoshima University Medical and Dental Hospital (Japan) between 2006 and 2013. Maxillary dental casts and facial photographs were taken at the time of the first visit and immediately prior to lip surgery to evaluate the maxillary arch and nasal form changes. The dental casts were scanned with a laser scanner, and changes in the 3-Dimensional coordinates of anatomical landmarks and alveolar cleft width were analysed. Moreover, we investigated the correlation between the changes in the maxillary alveolar arch and nasal form. Regarding the maxillary alveolar arch form, the anterior points of the major segment had moved significantly to the cleft side just prior to the time of lip repair, and the alveolar cleft width was significantly decreased. For nasal form, the inclination and displacement of the columella were significantly improved. The improvement of columella inclination was moderately correlated with the posterior movement of the anterior points of the major segment. These findings indicate that PNAM for infants with UCLP enhanced symmetry in the maxillary alveolar arch and nasolabial form. In addition, the posterior movement of the anterior points of the maxillary alveolar arch was correlated with the improvement of columella deformation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Correlation between hindfoot joint three-dimensional kinematics and the changes of the medial arch angle in stage II posterior tibial tendon dysfunction flatfoot.

PubMed

Zhang, Yi-Jun; Xu, Jian; Wang, Yue; Lin, Xiang-Jin; Ma, Xin

2015-02-01

The aim of this study was to explore the correlation between the kinematics of the hindfoot joint and the medial arch angle change in stage II posterior tibial tendon dysfunction flatfoot three-dimensionally under loading. Computed tomography (CT) scans of 12 healthy feet and 12 feet with stage II posterior tibial tendon dysfunction flatfoot were taken both in non- and full-body-weight-bearing condition. The CT images of the hindfoot bones were reconstructed into three-dimensional models with Mimics and Geomagic reverse engineering software. The three-dimensional changes of the hindfoot joint were calculated to determine their correlation to the medial longitudinal arch angle. The medial arch angle change was larger in stage II posterior tibial tendon dysfunction flatfoot compared to that in healthy foot under loading. The rotation and translation of the talocalcaneal joint, the talonavicular joint and the calcanocuboid joint had little influence on the change of the medial arch angle in healthy foot. However, the eversion of the talocalcaneal joint, the proximal translation of the calcaneus relative to the talus and the dorsiflexion of talonavicular joint could increase the medial arch angle in stage II posterior tibial tendon dysfunction flatfoot under loading. Joint instability occurred in patients with stage II posterior tibial tendon dysfunction flatfoot under loading. Limitation of over movement of the talocalcaneal joint and the talonavicular joint may help correct the medial longitudinal arch in stage II posterior tibial tendon dysfunction flatfoot. Copyright © 2014 Elsevier Ltd. All rights reserved.

Anatomic variations of the branches of the aortic arch in a Peruvian population.

PubMed

Huapaya, Julio Arturo; Chávez-Trujillo, Kristhy; Trelles, Miguel; Dueñas Carbajal, Roy; Ferrandiz Espadin, Renato

2015-07-31

Previous publications from two countries in South America found one anatomical variation not previously reported in the rest of the world, which in turn give some clues with regard to a racial difference. The objective of the present study is to describe variations in the anatomical distribution of the branches of the aortic arch in a Peruvian population. To describe variations in the anatomical distribution of the branches of the aortic arch in a Peruvian population. A descriptive study of patients who underwent a tomography angiography of the aorta was performed. We analyzed the reports that showed the description of the variations of the branches of the aortic arch based on the eight types currently described in the literature. From 361 analyzed reports, 282 patients (78.12%) had a normal aortic arch configuration (type I; aortic arch gives rise to the brachiocephalic trunk, left common carotid and left subclavian arteries); followed by type II (left common carotid artery as a branch of the aorta) with 41 patients (11.36%); and type IX (common ostium for the brachiocephalic trunk and the left common carotid artery) with 25 patients (6.93%). The latter and two other types are new variations. Aortic Arch Type I, Type II and Type IX were the most frequent variations in this Peruvian study. Additionally, we also found two more new types that have not been previously described in the literature. Further investigation regarding these variations is needed in order to assess a racial factor in South America and possible relationships with clinical or surgical events.

Influence of Custom Trays, Dual-Arch Passive, Flexed Trays and Viscosities of Elastomeric Impression Materials on Working Dies.

PubMed

Arora, Mansi; Kohli, Shivani; Kalsi, Rupali

2016-05-01

Dual arch impression technique signifies an essential improvement in fixed prosthodontics and has numerous benefits over conventional impression techniques. The accuracy of working dies fabricated from dual arch impression technique remains in question because there is little information available in the literature. This study was conducted to compare the accuracy of working dies fabricated from impressions made from two different viscosities of impression materials using metal, plastic dual arch trays and custom made acrylic trays. The study samples were grouped into two groups based on the viscosity of impression material used i.e. Group I (monophase), whereas Group II consisted of Dual Mix technique using a combination of light and heavy body material. These were further divided into three subgroups A, B and C depending on the type of impression tray used (metal dual arch tray, plastic dual arch tray and custom made tray). Measurements of the master cast were made using profile projector. Descriptive statistics like mean, Standard Deviation (SD) were calculated for all the groups. One way analysis of variance (ANOVA) was used for multiple group comparisons. A p-value of 0.05 or less was considered statistically significant. The gypsum dies obtained with the three types of impression trays using two groups of impression materials were smaller than the master models in dimensions. The plastic dual arch trays produced dies which were the least accurate of the three groups. There was no significant difference in the die dimensions obtained using the two viscosities of impression materials.

A comparative study on the stress distribution around dental implants in three arch form models for replacing six implants using finite element analysis.

PubMed

Zarei, Maryam; Jahangirnezhad, Mahmoud; Yousefimanesh, Hojatollah; Robati, Maryam; Robati, Hossein

2018-01-01

Dental implant is a method to replacement of missing teeth. It is important for replacing the missed anterior teeth. In vitro method is a safe method for evaluation of stress distribution. Finite element analysis as an in vitro method evaluated stress distribution around replacement of six maxillary anterior teeth implants in three models of maxillary arch. In this in vitro study, using ABAQUS software (Simulia Corporation, Vélizy-Villacoublay, France), implant simulation was performed for reconstruction of six maxillary anterior teeth in three models. Two implants were placed on both sides of the canine tooth region (A model); two implants on both sides of the canine tooth region and another on one side of the central incisor region (B model); and two implants on both sides of the canine tooth region and two implants in the central incisor area (C model). All implants evaluated in three arch forms (tapered, ovoid, and square). Data were analyzed by finite analysis software. Von Mises stress by increasing of implant number was reduced. In a comparison of A model in each maxillary arch, the stress created in the cortical and cancellous bones in the square arch was less than ovoid and tapered arches. The stress created in implants and cortical and cancellous bones in C model was less than A and B models. The C model (four-implant) reduced the stress distribution in cortical and cancellous bones, but this pattern must be evaluated according to arch form and cost benefit of patients.

Speech evaluation and dental arch shape following pushback palatoplasty in cleft palate patients: Supraperiosteal flap technique versus mucoperiosteal flap technique.

PubMed

Ito, Shizuyo; Noguchi, Makoto; Suda, Yoshiyuki; Yamaguchi, Akira; Kohama, Geniku; Yamamoto, Etsuhide

2006-04-01

The aim of this study was to evaluate and compare the maxillary dental arch shape and speech of cleft palate patients following pushback palatoplasty using either the supraperiosteal flap technique or the mucoperiosteal flap technique. Sixty-two patients (29, cleft palate only; 33, unilateral cleft lip, alveolus and palate) operated on by the supraperiosteal technique and 47 patients (23, cleft palate only; 24 unilateral cleft lip, alveolus and palate) by the mucoperiosteal technique were reviewed in this study. Dental arch shape and speech proficiency at preschool and school age were evaluated in all patients. Dental arch shapes were classified as U type (good dental arch shape) and V type (narrow dental arch shape). In cleft palate only patients, U type was observed in 90% of the supraperiosteal group and 83% of the mucoperiosteal group. In unilateral cleft lip, alveolus and palate patients, U type was observed in 85% of the supraperiosteal group, while only in 33% of the mucoperiosteal group. In cleft palate only patients, normal speech at school age was observed 100% of the supraperiosteal group and 83% of the mucoperiosteal group. In unilateral cleft lip, alveolus and palate patients, normal speech at school age was observed in 97% of the supraperiosteal group and 75% of the mucoperiosteal group. Misarticulation was frequently found in patients with the V type of dental arch shape. It is suggested that pushback palatoplasty using the supraperiosteal technique is more advantageous for speech development compared with the mucoperiosteal technique.

Influence of Custom Trays, Dual-Arch Passive, Flexed Trays and Viscosities of Elastomeric Impression Materials on Working Dies

PubMed Central

Kohli, Shivani; Kalsi, Rupali

2016-01-01

Introduction Dual arch impression technique signifies an essential improvement in fixed prosthodontics and has numerous benefits over conventional impression techniques. The accuracy of working dies fabricated from dual arch impression technique remains in question because there is little information available in the literature. Aim This study was conducted to compare the accuracy of working dies fabricated from impressions made from two different viscosities of impression materials using metal, plastic dual arch trays and custom made acrylic trays. Materials and Methods The study samples were grouped into two groups based on the viscosity of impression material used i.e. Group I (monophase), whereas Group II consisted of Dual Mix technique using a combination of light and heavy body material. These were further divided into three subgroups A, B and C depending on the type of impression tray used (metal dual arch tray, plastic dual arch tray and custom made tray). Measurements of the master cast were made using profile projector. Descriptive statistics like mean, Standard Deviation (SD) were calculated for all the groups. One way analysis of variance (ANOVA) was used for multiple group comparisons. A p-value of 0.05 or less was considered statistically significant. Results The gypsum dies obtained with the three types of impression trays using two groups of impression materials were smaller than the master models in dimensions. Conclusion The plastic dual arch trays produced dies which were the least accurate of the three groups. There was no significant difference in the die dimensions obtained using the two viscosities of impression materials. PMID:27437342

Dental arch dimensional changes after adenoidectomy or tonsillectomy in children with airway obstruction: A meta-analysis and systematic review under PRISMA guidelines.

PubMed

Zhu, Yanfei; Li, Jiaying; Tang, Yanmei; Wang, Xiaoling; Xue, Xiaochen; Sun, Huijun; Nie, Ping; Qu, Xinhua; Zhu, Min

2016-09-01

Children with severe airway obstruction tend to have a vertical direction of growth, class II malocclusion, and narrow arches. Adenoidectomy and tonsillectomy were recommended for the promotion of balanced dentition growth in these children.The aim of this study was to determine the effect of adenoidectomy and tonsillectomy on the growth of dental morphology in children with airway obstruction. A comprehensive search of the Medline, Embase, Web of science, and OVID databases for studies published through to January 17, 2016 was conducted. Prospective, comparative, clinical studies assessing the efficacy of adenoidectomy, or tonsillectomy in children with airway obstruction were included. The weighted mean difference (WMD) and 95% confidence interval (CI) were used for continuous variables. Forest plots were drawn to demonstrate effects in the meta-analyses. Eight papers were included in our study. We found that adenoidectomy and tonsillectomy led to a significant change in nasal-breathing in children with airway obstruction. Children with airway obstruction had a significantly narrower posterior maxillary dental arch than children without airway obstruction (WMD = -0.94, 95% CI [-1.13, -0.76]; P < 0.001). After surgery, these children still had a significantly narrower dental arch than the nasal-breathing children (WMD = -0.60, 95% CI [-0.79, -0.42]; P < 0.001). In terms of dental arch width, malocclusion, palatal height, overjet, overbite, dental arch perimeter, and arch length, a tendency toward normalization was evident following adenoidectomy or tonsillectomy, with no significant differences evident between the surgical group and the normal group. The small number of studies and lack of randomized controlled trials were the main limitations of this meta-analysis. Following adenoidectomy and tonsillectomy, the malocclusion and narrow arch width of children with airway obstruction could not be completely reversed. Therefore, other treatments such as functional training or orthodontic maxillary widening should be considered after removing the obstruction in the airway.

A radiographic and anthropometric study of the effect of a contoured sandal and foot orthosis on supporting the medial longitudinal arch.

PubMed

Escalona-Marfil, Carles; McPoil, Thomas G; Mellor, Rebecca; Vicenzino, Bill

2014-01-01

In-shoe foot orthoses improve conditions such as plantar heel pain (fasciitis), probably due to their ability to raise the medial longitudinal arch of the foot and lower the stress on the plantar tissues. Increasingly the arch-profile form of the in-shoe foot orthosis is being incorporated into sandal footwear, providing an alternative footwear option for those who require an orthosis. The purpose of this study was to evaluate if a sandal that incorporates the arch-profile of an in-shoe foot orthosis does indeed raise the medial longitudinal arch. Three commercially available non-medical devices (contoured and flat sandal, prefabricated in-shoe orthosis) worn by healthy individuals were studied in two independent experiments, one using radiographic measurements in Australia (n = 11, 6 female, age 26.1 ± 4.3 yrs, BMI 22.0 ± 2.4 kg/m(2)) and the other utilising anthropometric measures in the USA (n = 10, 6 female, age 26.3 ± 3.8 yrs, BMI 23.5 ± 3.7 kg/m(2)). A barefoot condition was also measured. Dorsal arch height was measured in both experiments, as well as in subtalar neutral in the anthropometric experiment. One way repeated measures ANOVA with follow up Bonferroni-corrected pairwise comparisons were used to test differences between the conditions (contoured and flat sandal, orthosis, barefoot). Mean difference and 95% confidence intervals (CI) and standardised mean differences (SMD) were also calculated. The contoured sandal significantly increased dorsal arch height compared to barefoot and flat sandal in both the anthropometric and radiographic experiments with SMD ranging from 0.95 (mean difference 5.1 mm (CI: 0.3, 1.6)) to 1.8 (4.3 mm (1.9, 6.6)). There were small differences between the contoured sandal and orthosis of 1.9 mm (0.6, 3.3) in the radiographic experiment and 1.2 mm (-0.4, 0.9) in the anthropometric experiment. The contoured sandal approximated the subtalar neutral position (0.4 mm (-0.5, 0.7)). Medial longitudinal arch height is elevated by contoured sandals and approximates subtalar joint neutral position of the foot and that achieved by an orthosis. Practitioners wanting to increase the medial longitudinal arch can do so with either an orthosis or a contoured sandal that includes the raised arch profile form of an orthosis.

Causes and occurrences of interruptions during ED triage.

PubMed

Johnson, Kimberly D; Motavalli, Michele; Gray, Dean; Kuehn, Connie

2014-09-01

Interruptions have been shown to cause errors and delays in the treatment of emergency patients and pose a real threat during the triage process. Missteps during the triage assessment can send a patient down the wrong treatment path and lead to delays. The purpose of this project was to identify the types and frequency of interruptions during the ED triage interview process. A focus group of emergency nurses was organized to identify the types of interruptions that commonly occur during the triage interview. These interruptions would be validated through observations in triage. A tally sheet was developed and implemented to determine how often each interruption occurred during an 8-hour shift. Triage nurses completed the tally sheets while working the first shift (7 am to 3 pm). This shift was selected because patient intake in the US Department of Veterans Affairs Emergency Department is highest during this time. The categories of interruptions identified included provision of conveniences to visitors, coworker-related interruptions, patient care-related interruptions, locating of family members in the emergency department, and other miscellaneous interruptions. Tally sheets were completed by the triage nurses during 10 shifts. On average, triage nurses were interrupted 48.2 times during an 8-hour shift (7 interruptions per hour). After reviewing the data, we found that only 22% of interruptions were related to patient care. More frequently, the causes of interruptions were not related to patient care: opening the door (33%), providing conveniences to visitors (21%), waiting patients or family members asking "How much longer?" (14%), and other causes (10%). Frequent interruptions can interfere with concentration and may affect patient care. Non-patient care-related interruptions not only can be frustrating to the triage nurse but also can be offensive to triage patients; they ultimately delay care and may even affect the quality of care. However, because scarce research is available regarding interruptions during ED triage, the effects on patient outcomes are unclear. Additional research needs to be conducted to explore the causes and effects of interruptions to the triage process. Copyright © 2014 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

Risk model of thoracic aortic surgery in 4707 cases from a nationwide single-race population through a web-based data entry system: the first report of 30-day and 30-day operative outcome risk models for thoracic aortic surgery.

PubMed

Motomura, Noboru; Miyata, Hiroaki; Tsukihara, Hiroyuki; Takamoto, Shinichi

2008-09-30

The objective of this study was to collect integrated data from nationwide hospitals using a web-based national database system to build up our own risk model for the outcome from thoracic aortic surgery. The Japan Adult Cardiovascular Surgery Database was used; this involved approximately 180 hospitals throughout Japan through a web-based data entry system. Variables and definitions are almost identical to the STS National Database. After data cleanup, 4707 records were analyzed from 97 hospitals (between January 1, 2000, and December 31, 2005). Mean age was 66.5 years. Preoperatively, the incidence of chronic lung disease was 11%, renal failure was 9%, and rupture or malperfusion was 10%. The incidence of the location along the aorta requiring replacement surgery (including overlapping areas) was: aortic root, 10%; ascending aorta, 47%; aortic arch, 44%; distal arch, 21%; descending aorta, 27%; and thoracoabdominal aorta, 8%. Raw 30-day and 30-day operative mortality rates were 6.7% and 8.6%, respectively. Postoperative incidence of permanent stroke was 6.1%, and renal failure requiring dialysis was 6.7%. OR for 30-day operative mortality was as follows: emergency or salvage, 3.7; creatinine >3.0 mg/dL, 3.0; and unexpected coronary artery bypass graft, 2.6. As a performance metric of the risk model, C-index of 30-day and 30-day operative mortality was 0.79 and 0.78, respectively. This is the first report of risk stratification on thoracic aortic surgery using a nationwide surgical database. Although condition of these patients undergoing thoracic aortic surgery was much more serious than other procedures, the result of this series was excellent.

Ticagrelor Versus Aspirin in Acute Embolic Stroke of Undetermined Source.

PubMed

Amarenco, Pierre; Albers, Gregory W; Denison, Hans; Easton, J Donald; Evans, Scott R; Held, Peter; Hill, Michael D; Jonasson, Jenny; Kasner, Scott E; Ladenvall, Per; Minematsu, Kazuo; Molina, Carlos A; Wang, Yongjun; Wong, K S Lawrence; Johnston, S Claiborne

2017-09-01

Ticagrelor is an effective antiplatelet therapy among patients with atherosclerotic disease and, therefore, could be more effective than aspirin in preventing recurrent stroke and cardiovascular events among patients with embolic stroke of unknown source (ESUS), which includes patients with ipsilateral stenosis <50% and aortic arch atherosclerosis. We randomized 13 199 patients with a noncardioembolic, nonsevere ischemic stroke or high-risk transient ischemic attack to ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2-90) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2-90) within 24 hours of symptom onset. In all patients, investigators informed on the presence of ipsilateral stenosis ≥50%, small deep infarct <15 mm, and on cardiac source of embolism detected after enrollment or rare causes, which allowed to construct an ESUS category in all other patients with documented brain infarction. The primary end point was the time to the occurrence of stroke, myocardial infarction, or death within 90 days. ESUS was identified in 4329 (32.8%) patients. There was no treatment-by-ESUS category interaction ( P =0.83). Hazard ratio in ESUS patients was 0.87 (95% confidence interval, 0.68-1.10; P =0.24). However, hazard ratio was 0.51 (95% confidence interval, 0.29-0.90; P =0.02) in ESUS patients with ipsilateral stenosis <50% or aortic arch atherosclerosis (n=961) and 0.98 (95% confidence interval, 0.76-1.27; P =0.89) in the remaining ESUS patients (n=3368; P for heterogeneity =0.04). In this post hoc, exploratory analysis, we found no treatment-by-ESUS category interaction. ESUS subgroups have heterogeneous response to treatment (Funded by AstraZeneca). URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720. © 2017 American Heart Association, Inc.

Cell Motility and Invasiveness of Neurofibromin-Deficient Neural Crest Cells and Malignant Triton Tumor Lines

DTIC Science & Technology

2005-06-01

derived cells, we isolated first branchial arch mesenchymal populations, as well as trigeminal ganglion non-neuronal cells, from mouse embryos and measured...demonstrate that loss of neurofibromin affects the invasiveness of neural crest-derived (trigeminal ganglion) and cranial mesenchymal ( branchial arch) cell...trigeminal and branchial arch cells between El0 and El 2 indicates that the roles of neurofibromin in controlling motility may become increasingly

Aortic Arch Aneurysms: Treatment with Extra anatomical Bypass and Endovascular Stent-Grafting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kato, Noriyuki; Shimono, Takatsugu; Hirano, Tadanori

2002-10-15

Endovascular repair of thoracic aortic aneurysms is emerging as an attractive alternative to surgical graft replacement. However,patients with aortic arch aneurysms are often excluded from the target of endovascular repair because of lack of suitable landing zones, especially at the proximal ones. In this paper we describe our method for treating patients with aortic arch aneurysms using a combination of extra anatomical bypass surgery and endovascular stent-grafting.

Structural safety evaluation of Gerber Arch Dam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barrie, R.E.

1995-12-31

Gerber Dam, a variable radius arch structure, has experienced seepage and extensive freeze-thaw damage since its construction. A construction key was found cracked at its crest. A finite element investigation was made to evaluate the safety of the arch structure. Design methods and assumptions are evaluated. Historical performance is used in the evaluation. Stress levels, patterns, and distributions were evaluated for loads the structure has experienced to determine behavior contributing to seepage and cracking.

Free in-plane vibration of circular arches.

NASA Technical Reports Server (NTRS)

Veletsos, A. S.; Austin, W. J.; Lopes Pereira, C. A.; Wung, S.-J.

1972-01-01

Numerical data are presented for the natural frequencies and modes of vibration of hinged and fixed, uniform, circular arches vibrating in their own plane, and the effects of the various parameters affecting the response are analyzed. It is shown that the vibrational modes may be almost purely flexural, or almost purely extensional, or the extensional and flexural actions may be strongly coupled. The conditions of occurrence of each type of behavior are defined, and simple approximate formulas are derived; using these formulas, the free vibrational characteristics of arches may be estimated to a satisfactory degree of accuracy for most practical applications. The approach used to derive the approximate formulas may also be applied to arches having other boundary conditions, shapes, or distributions of stiffness and mass.

Buckling of Low Arches or Curved Beams of Small Curvature

NASA Technical Reports Server (NTRS)

Fung, Y C; Kaplan, A

1952-01-01

A general solution, based on the classical buckling criterion, is given for the problem of buckling of low arches under a lateral loading acting toward the center of curvature. For a sinusoidal arch under sinusoidal loading, the critical load can be expressed exactly as a simple function of the beam dimension parameters. For other arch shapes and load distributions, approximate values of the critical load can be obtained by summing a few terms of a rapidly converging Fourier series. The effects of initial end thrust and axial and lateral elastic support are discussed. The buckling load based on energy criterion of Karman and Tsien is also calculated. Results for both the classical and the energy criteria are compared with experimental results.

Experimental performance of 75-millimeter-bore arched outer-race ball bearings to 2.1 million DN. [thrust loads

NASA Technical Reports Server (NTRS)

Coe, H. H.

1976-01-01

An experimental investigation was performed to determine the operating characteristics of arched outer-race bearings and to compare the data with those for a similar, but conventional, deep-groove ball bearing. The bearings were tested over a range of shaft speeds up to 28,000 rpm at a thrust load of 2200 newtons (500 lb). One bearing was operated at 26,000 rpm with a range of thrust loads. The amounts of arching were 0.13, 0.25, and 0.51 millimeter (0.005, 0.010, and 0.020 in.). All bearings operated satisfactorily; the arched bearing outer-race temperatures and torques were consistently higher than those for the conventional bearing.

Post-flare coronal arches observed with the SMM/XRP flat crystal spectrometer

NASA Technical Reports Server (NTRS)

Hick, Paul; Svestka, Zdenek; Smith, Kermit L.; Strong, Keith T.

1987-01-01

Postflare coronal arch observations made with the SMM Flat Crystal Spectrometer on January 20-23, 1985 are discussed. Results suggest that the arch revival following the dynamic flare of 23:50 UT on January 1 was of the type noted on November 6-8 and June 4, 1980 by the SMM Hard X-ray Imaging Spectrometer (HXIS). Activity different from that of the HXIS observations was found starting at about 23 UT on January 22, with no trigger of the revival being identified, and with the activity being restricted to the coronal regions (without any related disturbance in the chromosphere). The development of the arch enhancement in the corona was shown to be slower than is expected for a flare-associated revival.

Post-flare coronal arches observed with the SMM/XRP flat crystal spectrometer

NASA Astrophysics Data System (ADS)

Hick, Paul; Svestka, Zdenek; Smith, Kermit L.; Strong, Keith T.

1987-09-01

Postflare coronal arch observations made with the SMM Flat Crystal Spectrometer on January 20-23, 1985 are discussed. Results suggest that the arch revival following the dynamic flare of 23:50 UT on January 1 was of the type noted on November 6-8 and June 4, 1980 by the SMM Hard X-ray Imaging Spectrometer (HXIS). Activity different from that of the HXIS observations was found starting at about 23 UT on January 22, with no trigger of the revival being identified, and with the activity being restricted to the coronal regions (without any related disturbance in the chromosphere). The development of the arch enhancement in the corona was shown to be slower than is expected for a flare-associated revival.

Evaluation and Impact of Workflow Interruptions During Robot-assisted Surgery.

PubMed

Allers, Jenna C; Hussein, Ahmed A; Ahmad, Nabeeha; Cavuoto, Lora; Wing, Joseph F; Hayes, Robin M; Hinata, Nobuyuki; Bisantz, Ann M; Guru, Khurshid A

2016-06-01

To analyze and categorize causes for interruptions during robot-assisted surgery. We analyzed 10 robot-assisted prostatectomies that were performed by 3 surgeons from October 2014 to June 2015. Interruptions to surgery were defined in terms of duration, stage of surgery, personnel involved, reasons, and impact of the interruption on the surgical workflow. The main reasons for interruptions included the following: console surgeons switching (29%); preparation of the surgical equipment, such as cleaning or changing the camera (29%) or an instrument (27%); or when a suture, stapler, or clip was needed (12%). The most common interruption duration was 10-29 seconds (47.6%), and the least common interruption duration was greater than 90 seconds (3.6%). Additionally, about 14% of the interruptions were considered avoidable, whereas the remaining 86% of interruptions were necessary for surgery. By identifying and analyzing interruptions, we can develop evidence-based strategies to improve operating room efficiency, lower costs, and advance patient safety. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessment of teacher interruptions on learners during oral case presentations.

PubMed

Yang, Glen; Chin, Rachel

2007-06-01

Studies have only recently begun to investigate the effects of interruptions on physicians in the emergency department (ED). To determine the frequency and nature of interruptions by the training physician that occur when medical trainees do oral case presentations (OCPs) in the ED. This was an observational study. Learner OCPs to attending emergency physicians were observed in the ED of an urban Level 1 trauma center at a major teaching hospital. A single investigator followed attending physicians blinded to the study objective in a nonrandomized convenience sampling of all ED shifts, recording information regarding teacher interruptions during new patient presentations. Learners completed a brief questionnaire after each OCP. A total of 196 OCPs were observed. The mean (+/-SD) duration of OCPs was 3.30 (+/-1.85) minutes, and the mean (+/-SD) number of interruptions was 0.75 (+/-0.60) per minute and 2.49 (+/-1.95) per OCP. The number of interruptions (per OCP) and duration of OCP varied by learner level of training, with more experienced learners giving shorter presentations and being interrupted less often. Frequency (per minute) of interruptions did not vary by learner level. In 40.3% of OCPs, attending physicians interrupted to give an assessment and/or a plan before the learner had done so, but 8.3% of interrupted learners believed that teacher interruptions were "disruptive" to their OCP. Attending emergency physicians frequently interrupt learners during new patient OCPs, with the number of interruptions varying by learner level of training. Teacher interruptions appear to have minimal, if any, detrimental effect on the perceived effectiveness of OCPs as a learning experience.

Biology of biomechanics: Finite element analysis of a statically determinate system to rotate the occlusal plane for correction of a skeletal Class III open-bite malocclusion.

PubMed

Roberts, W Eugene; Viecilli, Rodrigo F; Chang, Chris; Katona, Thomas R; Paydar, Nasser H

2015-12-01

In the absence of adequate animal or in-vitro models, the biomechanics of human malocclusion must be studied indirectly. Finite element analysis (FEA) is emerging as a clinical technology to assist in diagnosis, treatment planning, and retrospective analysis. The hypothesis tested is that instantaneous FEA can retrospectively simulate long-term mandibular arch retraction and occlusal plane rotation for the correction of a skeletal Class III malocclusion. Seventeen published case reports were selected of patients treated with statically determinate mechanics using posterior mandible or infrazygomatic crest bone screw anchorage to retract the mandibular arch. Two-dimensional measurements were made for incisor and molar movements, mandibular arch rotation, and retraction relative to the maxillary arch. A patient with cone-beam computed tomography imaging was selected for a retrospective FEA. The mean age for the sample was 23.3 ± 3.3 years; there were 7 men and 10 women. Mean incisor movements were 3.35 ± 1.55 mm of retraction and 2.18 ± 2.51 mm of extrusion. Corresponding molar movements were retractions of 4.85 ± 1.78 mm and intrusions of 0.85 ± 2.22 mm. Retraction of the mandibular arch relative to the maxillary arch was 4.88 ± 1.41 mm. Mean posterior rotation of the mandibular arch was -5.76° ± 4.77° (counterclockwise). The mean treatment time (n = 16) was 36.2 ± 15.3 months. Bone screws in the posterior mandibular region were more efficient for intruding molars and decreasing the vertical dimension of the occlusion to close an open bite. The full-cusp, skeletal Class III patient selected for FEA was treated to an American Board of Orthodontics Cast-Radiograph Evaluation score of 24 points in about 36 months by en-masse retraction and posterior rotation of the mandibular arch: the bilateral load on the mandibular segment was about 200 cN. The mandibular arch was retracted by about 5 mm, posterior rotation was about 16.5°, and molar intrusion was about 3 mm. There was a 4° decrease in the mandibular plane angle to close the skeletal open bite. Retrospective sequential iterations (FEA animation) simulated the clinical response, as documented with longitudinal cephalometrics. The level of periodontal ligament stress was relatively uniform (<5 kPa) for all teeth in the mandibular arch segment. En-masse retraction of the mandibular arch is efficient for conservatively treating a skeletal Class III malocclusion. Posterior mandibular anchorage causes intrusion of the molars to close the vertical dimension of the occlusion and the mandibular plane angle. Instantaneous FEA as modeled here could be used to reasonably predict the clinical results of an applied load. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Control of cardiorespiratory function in response to hypoxia in an air-breathing fish, the African sharptooth catfish, Clarias gariepinus.

PubMed

Belão, T C; Zeraik, V M; Florindo, L H; Kalinin, A L; Leite, C A C; Rantin, F T

2015-09-01

We evaluated the role of the first pair of gill arches in the control of cardiorespiratory responses to normoxia and hypoxia in the air-breathing catfish, Clarias gariepinus. An intact group (IG) and an experimental group (EG, bilateral excision of first gill arch) were submitted to graded hypoxia, with and without access to air. The first pair of gill arches ablations reduced respiratory surface area and removed innervation by cranial nerve IX. In graded hypoxia without access to air, both groups displayed bradycardia and increased ventilatory stroke volume (VT), and the IG showed a significant increase in breathing frequency (fR). The EG exhibited very high fR in normoxia that did not increase further in hypoxia, this was linked to reduced O2 extraction from the ventilatory current (EO2) and a significantly higher critical O2 tension (PcO2) than the IG. In hypoxia with access to air, only the IG showed increased air-breathing, indicating that the first pair of gill arches excision severely attenuated air-breathing responses. Both groups exhibited bradycardia before and tachycardia after air-breaths. The fH and gill ventilation amplitude (VAMP) in the EG were overall higher than the IG. External and internal NaCN injections revealed that O2 chemoreceptors mediating ventilatory hypoxic responses (fR and VT) are internally oriented. The NaCN injections indicated that fR responses were mediated by receptors predominantly in the first pair of gill arches but VT responses by receptors on all gill arches. Receptors eliciting cardiac responses were both internally and externally oriented and distributed on all gill arches or extra-branchially. Air-breathing responses were predominantly mediated by receptors in the first pair of gill arches. In conclusion, the role of the first pair of gill arches is related to: (a) an elevated EO2 providing an adequate O2 uptake to maintain the aerobic metabolism during normoxia; (b) a significant bradycardia and increased fAB elicited by externally oriented O2 chemoreceptors; (c) increase in the ventilatory variables (fR and VAMP) stimulated by internally oriented O2 chemoreceptors. Copyright © 2015 Elsevier Inc. All rights reserved.

Testing Of Choiced Ceramics Cutting Tools At Irregular Interrupted Cut

NASA Astrophysics Data System (ADS)

Kyncl, Ladislav; Malotová, Šárka; Nováček, Pavel; Nicielnik, Henryk; Šoková, Dagmar; Hemžský, Pavel; Pitela, David; Holubjak, Jozef

2015-12-01

This article discusses the test of removable ceramic cutting inserts during machining irregular interrupted cut. Tests were performed on a lathe, with the preparation which simulated us the interrupted cut. By changing the number of plates mounted in a preparation it simulate us a regular or irregular interrupted cut. When with four plates it was regular interrupted cut, the remaining three variants were already irregular cut. It was examined whether it will have the irregular interrupted cutting effect on the insert and possibly how it will change life of inserts during irregular interrupted cut (variable delay between shocks).

Improvement of Thermal Interruption Capability in Self-blast Interrupting Chamber for New 245kV-50kA GCB

NASA Astrophysics Data System (ADS)

Shinkai, Takeshi; Koshiduka, Tadashi; Mori, Tadashi; Uchii, Toshiyuki; Tanaka, Tsutomu; Ikeda, Hisatoshi

Current zero measurements are performed for 245kV-50kA-60Hz short line fault (L90) interruption tests with a self-blast interrupting chamber (double volume system) which has the interrupting capability up to 245kV-50kA-50Hz L90. Lower L90 interruption capability is observed for longer arcing time although very high pressure rise is obtained. It may be caused by higher blowing temperature and lower blowing density for longer arcing time. Interruption criteria and a optimization method of the chamber design are discussed to improve L90 interruption capability with it. The new chambers are designed at 245kV-50kA-60Hz to improve gas density in thermal volume for long arcing time. 245kV-50kA-60Hz L90 interruptions are performed with the new chamber. The suggested optimization method is an efficient tool for the self-blast interrupting chamber design although study of computing methods is required to calculate arc conductance around current zero as a direct criterion for L90 interruption capability with higher accuracy.

Computational analysis of hybrid Norwood circulation with distal aortic arch obstruction and reverse Blalock-Taussig shunt.

PubMed

Ceballos, Andres; Argueta-Morales, I Ricardo; Divo, Eduardo; Osorio, Ruben; Caldarone, Christopher A; Kassab, Alain J; Decampli, William M

2012-11-01

The hemodynamics characteristics of the hybrid Norwood (HN) procedure differ from those of the conventional Norwood and are not fully understood. We present a multiscale model of HN circulation to understand local hemodynamics and effects of aortic arch stenosis and a reverse Blalock-Taussig shunt (RBTS) on coronary and carotid perfusion. Four 3-dimensional models of four HN anatomic variants were developed, with and without 90% distal preductal arch stenosis and with and without a 4-mm RBTS. A lumped parameter model of the circulation was coupled to a local 3-dimensional computational fluid dynamics model. Outputs from the lumped parameter model provided waveform boundary conditions for the computational fluid dynamics model. A 90% distal arch stenosis reduced pressure and net flow-rate through the coronary and carotid arteries by 30%. Addition of the RBTS completely restored pressure and flow rate to baseline in these vessels. Zones of flow stagnation, flow reversal, and recirculation in the presence of stenosis were rendered more orderly by addition of the RBTS. In the absence of stenosis, presence of the shunt resulted in extensive zones of disturbed flow within the RBTS and arch. We found that a 4-mm × 21-mm RBTS completely compensated for the effects of a 90% discrete stenosis of the distal aortic arch in the HN. Placed preventatively, the RBTS and arch displayed zones with thrombogenic potential showing recirculation and stagnation that persist for a substantial fraction of the cardiac cycle, indicating that anticoagulation should be considered with a prophylactic RBTS. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Shear and pressure under the first ray in neuropathic diabetic patients: Implications for support of the longitudinal arch.

PubMed

Davis, Brian; Crow, Mariam; Berki, Visar; Ciltea, Daniela

2017-02-08

To assess dynamic arch support in diabetic patients at risk for Charcot neuroarthopathy whose arch index has not yet shown overt signs of foot collapse. Two indirect measures of toe flexor activation (ratios: peak hallux pressure to peak metatarsal pressure - Ph/Pm; peak posterior hallux shear to peak posterior metatarsal shear - Sh/Sm) were obtained with a custom built system for measuring shear and pressure on the plantar surface of the foot during gait. In addition, the tendency of the longitudinal arch to flatten was measured by quantifying the difference in shear between the 1st metatarsal head and the heel (S flatten ) during the first half of the stance phase. Four stance phases from the same foot for 29 participants (16 control and 13 neuropathic diabetic) were assessed. The peak load ratio under the hallux (Ph/Pm) was significantly higher in the control group (2.10±1.08 versus 1.13±0.74, p=0.033). Similarly, Sh/Sm was significantly higher in the control group (1.87±0.88 versus 0.88±0.45, p=0.004). The difference in anterior shear under the first metatarsal head and posterior shear under the lateral heel (S flatten ) was significantly higher in the diabetic group (p<0.01). Together these findings demonstrate reduced plantar flexor activity in the musculature responsible for maintaining the longitudinal arch. With no significant difference in arch index between the two groups, but significant differences in Ph/Pm, Sh/Sm and S flatten the collective results suggest there are changes in muscle activity that precede arch collapse. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of section properties on load carrying capacity of 10m span precast concrete closed spandrel arch bridge with corrugated section

NASA Astrophysics Data System (ADS)

Ong, Chong Yong; Choong, Kok Keong; Miralimov, Mirzakhid

2017-10-01

Various precast concrete arch bridge systems have been developed since 1960's. The reinforced concrete section of these systems is solid rectangular which is not an efficient section. Inspired by the nature of banana tree trunk, a relatively new corrugated section of precast concrete arch bridge was introduced and patented in Malaysia in 2008. This folded plate section is an open section which tends to open under vehicular loading. Hence, effect of section properties on load carrying capacity of precast concrete closed spandrel arch bridge with corrugated section under vehicle loading is presented in this paper. The arch bridge model has a clear span of 10m with 2.5m, 3.0m and 3.5m clear rise. For the corrugated section dimension model, overall depth varies from 475mm to 575mm, top and bottom flange thickness varies from 135mm to 155mm and web thickness varies from 90mm to 120mm. Linear and non-linear computational analysis are carried out using 2D PLAXIS software (in longitudinal direction) and LUSAS software (in transverse direction). In longitudinal direction, the sagging moment in non-linear analysis increases approximately 18% compared to linear analysis for different rise span ratio. From the analysis results, as the rise of arch increases, the sagging moment and hogging moment increases, but the axial force decreases. Besides, as the overall depth of corrugated section increases, the internal forces of the arch also increase. In transverse direction, the maximum tensile stress of concrete at crown and haunch decreases as slenderness ratio increases.

Machine-learning phenotypic classification of bicuspid aortopathy.

PubMed

Wojnarski, Charles M; Roselli, Eric E; Idrees, Jay J; Zhu, Yuanjia; Carnes, Theresa A; Lowry, Ashley M; Collier, Patrick H; Griffin, Brian; Ehrlinger, John; Blackstone, Eugene H; Svensson, Lars G; Lytle, Bruce W

2018-02-01

Bicuspid aortic valves (BAV) are associated with incompletely characterized aortopathy. Our objectives were to identify distinct patterns of aortopathy using machine-learning methods and characterize their association with valve morphology and patient characteristics. We analyzed preoperative 3-dimensional computed tomography reconstructions for 656 patients with BAV undergoing ascending aorta surgery between January 2002 and January 2014. Unsupervised partitioning around medoids was used to cluster aortic dimensions. Group differences were identified using polytomous random forest analysis. Three distinct aneurysm phenotypes were identified: root (n = 83; 13%), with predominant dilatation at sinuses of Valsalva; ascending (n = 364; 55%), with supracoronary enlargement rarely extending past the brachiocephalic artery; and arch (n = 209; 32%), with aortic arch dilatation. The arch phenotype had the greatest association with right-noncoronary cusp fusion: 29%, versus 13% for ascending and 15% for root phenotypes (P < .0001). Severe valve regurgitation was most prevalent in root phenotype (57%), followed by ascending (34%) and arch phenotypes (25%; P < .0001). Aortic stenosis was most prevalent in arch phenotype (62%), followed by ascending (50%) and root phenotypes (28%; P < .0001). Patient age increased as the extent of aneurysm became more distal (root, 49 years; ascending, 53 years; arch, 57 years; P < .0001), and root phenotype was associated with greater male predominance compared with ascending and arch phenotypes (94%, 76%, and 70%, respectively; P < .0001). Phenotypes were visually recognizable with 94% accuracy. Three distinct phenotypes of bicuspid valve-associated aortopathy were identified using machine-learning methodology. Patient characteristics and valvular dysfunction vary by phenotype, suggesting that the location of aortic pathology may be related to the underlying pathophysiology of this disease. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Effects of foot orthoses with medial arch support and lateral wedge on knee adduction moment in patients with medial knee osteoarthritis.

PubMed

Dessery, Yoann; Belzile, Étienne; Turmel, Sylvie; Corbeil, Philippe

2017-08-01

There is contradictory evidence regarding whether the addition of medial arch supports to laterally wedged insoles reduces knee adduction moment, improves comfort, and reduces knee pain during the late stance phase of gait. To verify if such effects occur in participants with medial knee osteoarthritis. Randomized single-blinded study. Gait analysis was performed on 18 patients affected by medial knee osteoarthritis. Pain and comfort scores, frontal plane kinematics and kinetics of ankle, knee, and hip were compared in four conditions: without foot orthosis, with foot orthoses, with medial arch support, and with foot orthoses with medial arch support and lateral wedge insoles with 6° and 10° inclination. Lower-extremity gait kinetics were characterized by a significant decrease, greater than 6%, in second peak knee adduction moment in laterally wedged insole conditions compared to the other conditions ( p < 0.001; effect size = 0.6). No significant difference in knee adduction moment was observed between laterally wedged insole conditions. In contrast, a significant increase of 7% in knee adduction moment during the loading response was observed in the customized foot orthoses without lateral inclination condition ( p < 0.001; effect size = 0.3). No difference was found in comfort or pain ratings between conditions. Our study suggests that customized foot orthoses with a medial arch support may only be suitable for the management of medial knee osteoarthritis when a lateral wedge is included. Clinical relevance Our data suggest that customized foot orthoses with medial arch support and a lateral wedge reduce knee loading in patients with medial knee osteoarthritis (KOA). We also found evidence that medial arch support may increase knee loading, which could potentially be detrimental in KOA patients.

Dental prosthetic status and prosthetic needs of institutionalised elderly population in oldage homes of jabalpur city, madhya pradesh, India.

PubMed

Deogade, Suryakant C; Vinay, S; Naidu, Sonal

2013-12-01

Oral disorders are cumulative throughout life and hence unfavourable outcomes are likely to be greatest among the elderly. A descriptive cross-sectional study was conducted among institutionalized geriatric population in old-age homes of Jabalpur city, Madhya Pradesh, to assess their prosthetic status and prosthetic needs. A cross-sectional survey was conducted in all the four old-age homes of Jabalpur city, Madhya Pradesh state, India. All residents aged 60 years and above formed the study population. The recording of prosthetic status and prosthetic needs was carried out according to the World Health Organisation (WHO) Oral Health Assessment Form (1997). A total of 224 individuals were included in the study of which 123 were females and 101 were males. Seventy five percent of the females and 55 % of the males had no prostheses in their upper arch and 61 % of the females and 76 % of the males had no prostheses in their lower arch. More number of males presented with 'Bridges' in their upper arch when compared to females (P value = 0.006). Highest prosthetic need in males was multi-unit prosthesis (42 % in upper arch and 41 % in lower arch) whereas, females' required full prosthesis (39 % in both the upper arch and lower arches). Ageing presents some formidable challenges, particularly with the institutionalised. This study clearly demonstrates a high insufficiency of prosthetic care among the institutionalized elderly population. Any preparation towards the provision of oral health care should not be limited to treatment alone but, more importantly focus on empowering this elderly community with information and education programmes.

Single center experience of aortic bypass graft for aortic arch obstruction in children.

PubMed

Shinkawa, Takeshi; Chipman, Carl; Holloway, Jessica; Tang, Xinyu; Gossett, Jeffrey M; Imamura, Michiaki

2017-01-01

The purpose of this study is to access the outcomes of aortic bypass graft placement in children. This is a retrospective review of all children having aortic bypass graft placement for aortic arch obstruction for the first time between 1982 and 2013 at a single institution. The actuarial survival and the freedom from aortic arch reoperation were calculated and compared between the groups. Seventy consecutive children underwent aortic bypass graft placements. The median age and body weight at the operation were 14 days and 3.6 kg. There were 7 early deaths, 6 late deaths, and 7 heart transplants during the median follow-up of 10.8 years (0.0-31.5 years). The actuarial transplant free survival was 64.7 % at 20 years and the freedom from aortic arch reoperation was 50.5 % at 10 years. Between the children younger than 1 year old and older than 1 year old, there were significant differences in actuarial transplant free survival (56.4 vs. 100 % at 15 years, p = 0.0042) and in the freedom from aortic arch reoperation (18.7 vs. 100 % at 10 years, p < 0.001). The children who received aortic bypass graft larger than 16 mm in size had no aortic arch reoperation at 15 years. The aortic bypass graft placement for aortic arch obstruction can be done with low mortality and morbidity for children who can receive bypass graft larger than 16 mm in size. However, it should be avoided for the neonates and infants except selected situations.

Pain and discomfort experienced after placement of a conventional or a superelastic NiTi aligning archwire. A randomized clinical trial.

PubMed

Fernandes, L M; Ogaard, B; Skoglund, L

1998-01-01

Two nickel-titanium arch-wire types commonly used for initial tooth alignment were compared with regard to the pain/discomfort patients experience during the initial phase of tooth movement. The two arch wires used were a superelastic nickel-titanium alloy, 0.014 inch Sentalloy, Light (GAC International Inc. Central Islip, NY, USA) and a 0.014 inch Nitinol (Unitek, Monrovia, CA, USA), a conventional nickel-titanium aligning archwire. One hundred and twenty-eight consecutive patients attending an orthodontic university clinic and 2 private practices for routine placement of a fixed appliance were randomly assigned one of these 2 initial arch wires. Assessments of pain/discomfort were made daily by means of a 100 mm visual analog scale (VAS) over the first 7-day period after bonding. On the first day, recordings were made every hour for the first 11 hours. The results showed that the level of discomfort increased continuously every hour after the insertion of either a Sentalloy or a Nitinol as first arch wires, with a peak in the first night, remaining high on the second day and decreasing thereafter to baseline level after 7 days. During the first 10 hours it was apparent that the pain/discomfort experienced after placement of a Sentalloy was less than that found with the Nitinol archwire, although a significant difference could be found at 4 hours only. No significant gender-specific differences were found in either archwire group. A significant difference between the upper and lower dental arches was observed during the first 11 hours after placement of either a Sentalloy or a Nitinol arch wire, with the lower arch having the higher pain experience.

The influence of the lateral pharyngeal wall anatomy on snoring and sleep apnoea.

PubMed

Korhan, Ibrahim; Gode, Sercan; Midilli, Rasit; Basoglu, Ozen Kacmaz

2015-02-01

To elucidate the variations of the lateral pharyngeal wall anatomy on physical examination and to assess the clinical importance of the examination of the lateral pharyngeal wall on the presence and severity of obstructive sleep apnoea syndrome. The cross-sectional study was conducted at Ege University Medical School, Izmir, Turkey, between May 2010 and April 2011. The patients were divided into four equal groups: Group 1--snoring without apnoea (age 20-40); Group 2--snoring without apnoea (age 40-60); Group 3--apnoea-hypopnoea index < 5/hr; Group 4: apnoea-hypopnoea index > 30/hr. Calibrated oropharynx pictures were taken. Distance between palatoglossal and palatopharyngeal arches, height of palatoglossal and palatopharyngeal arches, uvula width, uvula length and distance between tonsils were measured. SPSS 17 was used for statistical analysis. Of the 80 patients in the study, 44 (55%) were men. Mean distance between palatopharyngeal and palatoglossal arches were 1.55 ± 0.34 cm and 2.70 ± 0.43 cm respectively. Mean height of palatopharyngeal and palatoglossal arches were 0.60 ± 0.21 cm and 1.37 ± 0.36 cm respectively (p > 0.05). Mean uvula width and uvula length were 0.80 ± 0.12cm and 1.25 ± 0.27 cm respectively (p > 0.05). Mean distance between tonsils was 2.24 ± 0.56 cm (p > 0.05). Distance between palatopharyngeal arches was significantly different between groups 3 and 4 (p < 0.05). Palatopharyngeal arch anatomy was found to be significantly associated with obstructive sleep apnoea syndrome severity, especially in patients with normal or small tonsil size. Patients with the palatopharyngeal arches, which narrow the oropharyngeal inlet more than the tonsils, should further be investigated with polysomnography.

Aldosterone and parathyroid hormone interactions as mediators of metabolic and cardiovascular disease.

PubMed

Tomaschitz, Andreas; Ritz, Eberhard; Pieske, Burkert; Rus-Machan, Jutta; Kienreich, Katharina; Verheyen, Nicolas; Gaksch, Martin; Grübler, Martin; Fahrleitner-Pammer, Astrid; Mrak, Peter; Toplak, Hermann; Kraigher-Krainer, Elisabeth; März, Winfried; Pilz, Stefan

2014-01-01

Inappropriate aldosterone and parathyroid hormone (PTH) secretion is strongly linked with development and progression of cardiovascular (CV) disease. Accumulating evidence suggests a bidirectional interplay between parathyroid hormone and aldosterone. This interaction may lead to a disproportionally increased risk of CV damage, metabolic and bone diseases. This review focuses on mechanisms underlying the mutual interplay between aldosterone and PTH as well as their potential impact on CV, metabolic and bone health. PTH stimulates aldosterone secretion by increasing the calcium concentration in the cells of the adrenal zona glomerulosa as a result of binding to the PTH/PTH-rP receptor and indirectly by potentiating angiotensin 2 induced effects. This may explain why after parathyroidectomy lower aldosterone levels are seen in parallel with improved cardiovascular outcomes. Aldosterone mediated effects are inappropriately pronounced in conditions such as chronic heart failure, excess dietary salt intake (relative aldosterone excess) and primary aldosteronism. PTH is increased as a result of (1) the MR (mineralocorticoid receptor) mediated calciuretic and magnesiuretic effects with a trend of hypocalcemia and hypomagnesemia; the resulting secondary hyperparathyroidism causes myocardial fibrosis and disturbed bone metabolism; and (2) direct effects of aldosterone on parathyroid cells via binding to the MR. This adverse sequence is interrupted by mineralocorticoid receptor blockade and adrenalectomy. Hyperaldosteronism due to klotho deficiency results in vascular calcification, which can be mitigated by spironolactone treatment. In view of the documented reciprocal interaction between aldosterone and PTH as well as the potentially ensuing target organ damage, studies are needed to evaluate diagnostic and therapeutic strategies to address this increasingly recognized pathophysiological phenomenon. © 2013.

Social technology restriction alters state-anxiety but not autonomic activity in humans.

PubMed

Durocher, John J; Lufkin, Kelly M; King, Michelle E; Carter, Jason R

2011-12-01

Social technology is extensively used by young adults throughout the world, and it has been suggested that interrupting access to this technology induces anxiety. However, the influence of social technology restriction on anxiety and autonomic activity in young adults has not been formally examined. Therefore, we hypothesized that restriction of social technology would increase state-anxiety and alter neural cardiovascular regulation of arterial blood pressure. Twenty-one college students (age 18-23 yr) were examined during two consecutive weeks in which social technology use was normal or restricted (randomized crossover design). Mean arterial pressure (MAP), heart rate, and muscle sympathetic nerve activity (MSNA) were measured at rest and during several classic autonomic stressors, including isometric handgrip, postexercise muscle ischemia, cold pressor test, and mental stress. Tertile analysis revealed that restriction of social technology was associated with increases (12 ± 2 au; range 5 to 21; n = 7), decreases (-6 ± 2 au; range -2 to -11; n = 6), or no change (0 ± 0 au; range -1 to 3; n = 8) in state-anxiety. Social technology restriction did not alter MAP (74 ± 1 vs. 73 ± 1 mmHg), heart rate (62 ± 2 vs. 61 ± 2 beats/min), or MSNA (9 ± 1 vs. 9 ± 1 bursts/min) at rest, and it did not alter neural or cardiovascular responses to acute stressors. In conclusion, social technology restriction appears to have an interindividual influence on anxiety, but not autonomic activity. It remains unclear how repeated bouts, or chronic restriction of social technology, influence long-term psychological and cardiovascular health.

The influence of bracket design on frictional losses in the bracket/arch wire system.

PubMed

Schumacher, H A; Bourauel, C; Drescher, D

1999-01-01

In arch guided tooth movement, the essential role played by bracket configuration with respect to sliding friction has been recognized by the manufacturers, a fact which has had an increasing impact on the design and marketing of new bracket models in recent years. The aim of the present in-vitro study was to investigate the influence of different bracket designs on sliding mechanics. Five differently shaped stainless steel brackets (Discovery: Dentaurum, Damon SL: A-Company, Synergy: Rocky Mountain Orthodontics, Viazis bracket and Omni Arch appliance: GAC) were compared in the 0.022"-slot system. The Orthodontic Measurement and Simulation System (OMSS) was used to quantify the difference between applied force (NiTi coil spring, 1.0 N) and orthodontically effective force and to determine leveling losses occurring during the sliding process in arch guided tooth movement. Simulated canine retraction was performed using continuous arch wires with the dimensions 0.019" x 0.025" (Standard Steel, Unitek) and 0.020" x 0.020" (Ideal Gold, GAC). Comparison of the brackets revealed friction-induced losses ranging from 20 to 70%, with clear-cut advantages resulting from the newly developed bracket types. However, an increased tendency towards leveling losses in terms of distal rotation (maximum 15 degrees) or buccal root torque (maximum 20 degrees) was recorded, especially with those brackets giving the arch wire increased mobility due to their shaping or lack of ligature wire.

Histone deacetylase 1 and 2 are essential for murine neural crest proliferation, pharyngeal arch development, and craniofacial morphogenesis.

PubMed

Milstone, Zachary J; Lawson, Grace; Trivedi, Chinmay M

2017-12-01

Craniofacial anomalies involve defective pharyngeal arch development and neural crest function. Copy number variation at 1p35, containing histone deacetylase 1 (Hdac1), or 6q21-22, containing Hdac2, are implicated in patients with craniofacial defects, suggesting an important role in guiding neural crest development. However, the roles of Hdac1 and Hdac2 within neural crest cells remain unknown. The neural crest and its derivatives express both Hdac1 and Hdac2 during early murine development. Ablation of Hdac1 and Hdac2 within murine neural crest progenitor cells cause severe hemorrhage, atrophic pharyngeal arches, defective head morphogenesis, and complete embryonic lethality. Embryos lacking Hdac1 and Hdac2 in the neural crest exhibit decreased proliferation and increased apoptosis in both the neural tube and the first pharyngeal arch. Mechanistically, loss of Hdac1 and Hdac2 upregulates cyclin-dependent kinase inhibitors Cdkn1a, Cdkn1b, Cdkn1c, Cdkn2b, Cdkn2c, and Tp53 within the first pharyngeal arch. Our results show that Hdac1 and Hdac2 function redundantly within the neural crest to regulate proliferation and the development of the pharyngeal arches by means of repression of cyclin-dependent kinase inhibitors. Developmental Dynamics 246:1015-1026, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Body surface area as a key determinant of aortic root and arch dimensions in a population-based study.

PubMed

Wang, Yan-Li; Wang, Qing-Ling; Wang, Liang; Wu, Ying-Biao; Wang, Zhi-Bin; Cameron, James; Liang, Yu-Lu

2013-02-01

The associations between the aortic dimensions (of the aortic sinus, aortic annulus and aortic arch) and physiological variables have not been established in the Chinese population. The present study examined the associations among physiological variables to determine the aortic root and arch dimensions echocardiographically. The diameters of the aortic sinus, annulus and arch were measured in 1,010 subjects via 2-D echocardiography with a 3.5-MHz transducer in a trans-thoracic position. The images of the aortic sinus and aortic annulus were obtained from a standard parasternal long-axis view. The maximum diameter of the valve orifice was measured at the end of systole. The aortic arch dimension was visualized in the long-axis using a suprasternal notch window and the maximum transverse diameter was measured. Epidata 3.0, Excel 2007 and SPSS version 17.0 were used to collect and analyze the data. A total of 1,010 subjects were enrolled. The mean age was 55.0±17.0 years (range of 18 to 90 years). The body surface area (BSA) was the best predictor of all the studied physiological variables and may be used to predict aortic sinus, annulus and arch dimensions independently (r=0.54, 0.37 and 0.39, respectively). Gender, blood pressure, age and BSA are significant predictors of the aortic dimensions. Of these, BSA was the best predictor.

Design and application of hybrid maxillomandibular fixation for facial bone fractures.

PubMed

Park, Kang-Nam; Oh, Seung-Min; Lee, Chang-Youn; Kim, Jwa-Young; Yang, Byoung-Eun

2013-01-01

A novel maxillomandibular fixation (MMF) procedure using a skeletal anchorage screw (SAS) (in the maxilla) and an arch bar (in the mandible), which we call "hybrid maxillomandibular fixation," was explored in this study. The aims of the study were to examine the efficacy of our hybrid MMF method and to compare periodontal tissue health and occlusal rehabilitation among 3 MMF methods. In total, 112 patients who had undergone open reduction at the Department of Oral and Maxillofacial Surgery between September 2005 and December 2012 were selected for this study. The participants were assigned to one of the following groups: SAS (maxilla), SAS (mandible), SAS-arch bar, or arch bar-arch bar. Periodontal health was evaluated using the Gingival Index, and the perioperative occlusal reproducibility was evaluated using a score of 1 to 3. Statistical analysis was performed using parametric tests (Student t test or 1-way analysis of variance followed by post hoc Tukey test). In the Gingival Index comparison performed 1 month after the surgery, only the group using the arch bars and wiring was significantly different from the other groups (P < 0.05). The occlusal reproducibility scores were not significantly different. The pain and discomfort of the patients were reduced in the hybrid MMF group. The hybrid MMF takes advantage of MMF using both arch bars and SASs for mandibular fractures. In addition, it overcomes many problems presented by previous MMF methods.

[Function of the acetabulum of digenetic trematodes, as exemplified by Dicrocoelium dendriticum].

PubMed

Neuhaus, W

1985-01-01

The suckers of animals adhere to the substratum either in air or in aqueous fluids. The varying compressibility of these media causes differences in function, the principles of which are described. The ventral arch of the acetabulum of Dicrocoelium dendriticum, like the remaining body, is limited by the integument, basal lamina and skin muscles. The dorsal arch covers a basal lamina, which is close to a plexus of diagonal, longitudinal and circular muscles. The radical muscles, attached at the ventral basal lamina by thin connective tissue, continue in relatively thick contractile fibers, which split up into several fibrils, which also attached by thin connective tissue at the dorsal basal lamina. In this way the tension of the muscles is likewise distributed over the dorsal and ventral arches of the acetabulum. After contact with the substratum the sucker creates a partial vacuum and attachment by means of the pressure of the radial muscles against the wall of the hole. Because of the fluid content of the hole, the volume does not change much. The dorsal arch of the sucker withstands the pressure of the radical muscles, because its surface area is six times greater than that of the ventral arch and consequently the load is six times less. The sucker, covered with basal lamina, has a constant volume; its layer of muscles resists deformation and supports the stability of the arch.

Dental arch dimensional changes after adenotonsillectomy in prepubertal children.

PubMed

Petraccone Caixeta, Anna Cristina; Andrade, Ildeu; Bahia Junqueira Pereira, Tatiana; Franco, Letícia Paiva; Becker, Helena Maria Gonçalves; Souki, Bernardo Quiroga

2014-04-01

The purposes of this study were to investigate the dental arch changes after adenotonsillectomies in prepubertal children and to compare the dental arch dimensions of mouth-breathing and nasal-breathing children. The sample included 49 prepubertal severely obstructed mouth-breathing children and 46 prepubertal nasal-breathing children. Twenty-four of the 49 mouth-breathing children had an adenotonsillectomy and composed the adenotonsillectomy subgroup. The 25 children in whom the mouth-breathing pattern was unchanged during the 1-year study period composed the control subgroup. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. After airway clearance, the adenotonsillectomy group showed a significant maxillary transverse width gain compared with the control subgroup. The control subgroup showed a significant deepening of the palatal height when compared with the adenotonsillectomy subgroup after 1 year. The adenotonsillectomy subgroup had a significantly different pattern of arch development compared with the untreated controls. After adenotonsillectomy, the mouth-breathing children showed greater maxillary transverse development than did the controls. The palatal vault deepened in the untreated children. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Applicability of the Tanaka-Johnston and Moyers mixed dentition analyses in Northeast Han Chinese.

PubMed

Sherpa, Jangbu; Sah, Gopal; Rong, Zeng; Wu, Lipeng

2015-06-01

To assess applicability of the Tanaka-Johnston and Moyers prediction methods in a Han ethnic group from Northeast China and to develop prediction equations for this same population. Cross-sectional study. Department of Orthodontics, School of Stomatology, Jiamusi University, Heilongjiang, China. A total of 130 subjects (65 male and 65 female) aged 16-21 years from a Han ethnic group of Northeast China were recruited from dental students and patients seeking orthodontic treatment. Ethnicity was verified by questionnaire. Mesio-distal tooth width was measured using Digital Vernier calipers. Predicted values were obtained from the Tanaka-Johnston and Moyers methods in both arches were compared with the actual measured widths. Based on regression analysis, prediction equations were developed. Tanaka-Johnston equations were not precise, except for the upper arch in males. However, the Moyers 85th percentile in the upper arch and 75th percentile in the lower arch predicted the sum precisely in males. For females, the Moyers 75th percentile predicted the sum precisely for the upper arch, but none of the Moyers percentiles predicted in the lower arch. Both the Tanaka-Johnston and Moyers method may not be applied universally without question. Hence, it may be safer to develop regression equations for specific populations. Validating studies must be conducted to confirm the precision of these newly developed regression equations.

Detection of orthopaedic implants by airport metal detectors.

PubMed

Obremskey, William T; Austin, Tom; Crosby, Colin; Driver, Robin; Kurtz, Will; Shuler, Franklin; Kregor, Philip

2007-02-01

To report the effect of patient's body mass index (BMI), implant type, size, location, number, and material on detection by certified Transportation Security Administration (TSA) and Federal Aviation Administration (FAA) airport metal detectors set to today's standard sensitivity. Retrospective clinical study. Level 1 university trauma center. Ninety-six regularly scheduled trauma clinic patients with a wide variety of orthopaedic implants were enrolled in the study from August 2004 through December 2004. Patients walked through an airport arch metal detector and were also wanded with a handheld metal detector. Detection of implants by arch detector or wand was recorded. We also gathered information regarding BMI, location of implants, type, metal composition, and size. All unilateral prostheses (8/8) and bilateral prostheses (1/1) were detected. Subjects with 4 or fewer screws and no other implants were never detected by the arch metal detector (0/7). For the remaining 78 subjects, the 2 best predictors of detection by the arch were having plates of length >10 holes and having titanium nails (P < 0.001 for each predictor, Wald's test for effects in a logistic model). Prostheses, plates of length >10 holes, and titanium nails were the best predictors of detection by the arch. These 3 factors accounted for 42 of the 43 detections by the arch. Body mass index was not shown to affect detectability of orthopaedic implants.

Foreland uplift during flat subduction: Insights from the Peruvian Andes and Fitzcarrald Arch

NASA Astrophysics Data System (ADS)

Bishop, Brandon T.; Beck, Susan L.; Zandt, George; Wagner, Lara S.; Long, Maureen D.; Tavera, Hernando

2018-04-01

Foreland deformation has long been associated with flat-slab subduction, but the precise mechanism linking these two processes remains unclear. One example of foreland deformation corresponding in space and time to flat subduction is the Fitzcarrald Arch, a broad NE-SW trending topographically high feature covering an area of >4 × 105 km2 in the Peruvian Andean foreland. Recent imaging of the southern segment of Peruvian flat slab shows that the shallowest part of the slab, which corresponds to the subducted Nazca Ridge northeast of the present intersection of the ridge and the Peruvian trench, extends up to and partly under the southwestern edge of the arch. Here, we evaluate models for the formation of this foreland arch and find that a basal-shear model is most consistent with observations. We calculate that 5 km of lower crustal thickening would be sufficient to generate the arch's uplift since the late Miocene. This magnitude is consistent with prior observations of unusually thickened crust in the Andes immediately south of the subducted ridge that may also have been induced by flat subduction. This suggests that the Fitzcarrald Arch's formation by the Nazca Ridge may be one of the clearest examples of upper plate deformation induced through basal shear observed in a flat-slab subduction setting. We then explore the more general implications of our results for understanding deformation above flat slabs in the geologic past.

66. CORBELS, BLIND ARCHES & SHIELDS, COMMONS EAST WALL, LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

66. CORBELS, BLIND ARCHES & SHIELDS, COMMONS EAST WALL, LOOKING EAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

Overhead spine arch analysis of dairy cows from three-dimensional video

NASA Astrophysics Data System (ADS)

Abdul Jabbar, K.; Hansen, M. F.; Smith, M. L.; Smith, L. N.

2017-02-01

We present a spine arch analysis method in dairy cows using overhead 3D video data. This method is aimed for early stage lameness detection. That is important in order to allow early treatment; and thus, reduce the animal suffering and minimize the high forecasted financial losses, caused by lameness. Our physical data collection setup is non-intrusive, covert and designed to allow full automation; therefore, it could be implemented on a large scale or daily basis with high accuracy. We track the animal's spine using shape index and curvedness measure from the 3D surface as she walks freely under the 3D camera. Our spinal analysis focuses on the thoracic vertebrae region, where we found most of the arching caused by lameness. A cubic polynomial is fitted to analyze the arch and estimate the locomotion soundness. We have found more accurate results by eliminating the regular neck/head movements' effect from the arch. Using 22-cow data set, we are able to achieve an early stage lameness detection accuracy of 95.4%.

Class II malocclusion with complex problems treated with a novel combination of lingual orthodontic appliances and lingual arches.

PubMed

Yanagita, Takeshi; Nakamura, Masahiro; Kawanabe, Noriaki; Yamashiro, Takashi

2014-07-01

This case report describes a novel method of combining lingual appliances and lingual arches to control horizontal problems. The patient, who was 25 years of age at her first visit to our hospital with a chief complaint of crooked anterior teeth, was diagnosed with skeletal Class II and Angle Class II malocclusion with anterior deep bite, lateral open bite, premolar crossbite, and severe crowding in both arches. She was treated with premolar extractions and temporary anchorage devices. Conventionally, it is ideal to use labial brackets simultaneously with appliances, such as a lingual arch, a quad-helix, or a rapid expansion appliance, in patients with complex problems requiring horizontal, anteroposterior, and vertical control; however, this patient strongly requested orthodontic treatment with lingual appliances. A limitation of lingual appliances is that they cannot be used with other conventional appliances. In this report, we present the successful orthodontic treatment of a complex problem using modified lingual appliances that enabled combined use of a conventional lingual arch. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Numerical magnetohydrodynamic simulations of expanding flux ropes: Influence of boundary driving

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tacke, Thomas; Dreher, Jürgen; Sydora, Richard D.

2013-07-15

The expansion dynamics of a magnetized, current-carrying plasma arch is studied by means of time-dependent ideal MHD simulations. Initial conditions model the setup used in recent laboratory experiments that in turn simulate coronal loops [J. Tenfelde et al., Phys. Plasmas 19, 072513 (2012); E. V. Stenson and P. M. Bellan, Plasma Phys. Controlled Fusion 54, 124017 (2012)]. Boundary conditions of the electric field at the “lower” boundary, intersected by the arch, are chosen such that poloidal magnetic flux is injected into the domain, either localized at the arch footpoints themselves or halfway between them. These conditions are motivated by themore » tangential electric field expected to exist in the laboratory experiments due to the external circuit that drives the plasma current. The boundary driving is found to systematically enhance the expansion velocity of the plasma arch. While perturbations at the arch footpoints also deform its legs and create characteristic elongated segments, a perturbation between the footpoints tends to push the entire structure upwards, retaining an ellipsoidal shape.« less

Fgfr1 regulates patterning of the pharyngeal region

PubMed Central

Trokovic, Nina; Trokovic, Ras; Mai, Petra; Partanen, Juha

2003-01-01

Development of the pharyngeal region depends on the interaction and integration of different cell populations, including surface ectoderm, foregut endoderm, paraxial mesoderm, and neural crest. Mice homozygous for a hypomorphic allele of Fgfr1 have craniofacial defects, some of which appeared to result from a failure in the early development of the second branchial arch. A stream of neural crest cells was found to originate from the rhombomere 4 region and migrate toward the second branchial arch in the mutants. Neural crest cells mostly failed to enter the second arch, however, but accumulated in a region proximal to it. Both rescue of the hypomorphic Fgfr1 allele and inactivation of a conditional Fgfr1 allele specifically in neural crest cells indicated that Fgfr1 regulates the entry of neural crest cells into the second branchial arch non-cell-autonomously. Gene expression in the pharyngeal ectoderm overlying the developing second branchial arch was affected in the hypomorphic Fgfr1 mutants at a stage prior to neural crest entry. Our results indicate that Fgfr1 patterns the pharyngeal region to create a permissive environment for neural crest cell migration. PMID:12514106

Saccular aortic aneurysm that resembled a mediastinal neoplasm

PubMed Central

Nose, Naohiro; Kataoka, Hiroumi; Hamada, Masakatsu; Kosako, Yukio; Matsuno, Yasuji; Ishii, Takahiro

2012-01-01

INTRODUCTION Saccular aortic arch aneurysms in unusual sites may be misdiagnosed as a neoplasm. We present the case of a rare saccular aortic arch aneurysm between trachea and esophagus that resembled a mediastinal neoplasm in the preoperative findings. PRESENTATION OF CASE A 63-year-old male with an abnormal mediastinal shadow on chest X-ray was referred to the hospital. An axial plain computed tomogram of the chest revealed mediastinal soft tissue next to the right side of the aortic arch resembling a neoplasm originating from the gap between the trachea and the esophagus. The coronal view constructed by enhanced 64-row multi detector computed tomography revealed the soft tissue was an aneurysm arising from the inner side of the aortic arch. An aortic arch replacement was performed via a median sternotomy. DISCUSSION A thoracic aortic aneurysm sometimes behaves like a mediastinal neoplasm. The multiple cross-sectional image from multidetector computed tomography was useful for the correct diagnosis of such an aneurysm. CONCLUSION The possibility of an aneurysm should be considered whenever a mass in contact with the aortic wall is identified. PMID:22995656

The impact of foot arch height on quality of life in 6-12 year olds.

PubMed

López López, Daniel; Bouza Prego, M de Los Ángeles; Requeijo Constenla, Ana; Saleta Canosa, Jesús Luis; Bautista Casasnovas, Adolfo; Tajes, Francisco Alonso

2014-01-01

To determine whether arch height has an effect on the health-related quality of life of schoolchildren. One hundred and thirteen schoolchildren attended an out-patient centre where self-reported data were recorded, their feet were classified into one of three groups according to their arch index (high, normal or low) and the scores obtained from the Foot Health Status Questionnaire (FHSQ - Spanish version) were compared. The groups with high, low and normal arch recorded lower scores in Section One for the general foot health and footwear domains and higher scores in foot pain and foot function. In Section Two they obtained lower scores in general health and higher scores in physical activity, social capacity and vigour. Comparison of the scores obtained reveals that arch height has a negative impact on quality of life. Given the limited extent of available evidence in respect of the aetiology and treatment of foot diseases and deformities, these findings reveal the need to implement programmes to promote foot health and carry out further research into this commonly occurring disabling condition.

One-stage closure of isolated cleft palate with the Veau-Wardill-Kilner V to Y pushback procedure or the Cronin modification. II. Height, weight and comparison of dental arches.

PubMed

Heliövaara, A; Pere, A; Ranta, R

1994-03-01

The body height and weight, and sizes of dental arches in 116 patients with isolated cleft palate were evaluated at 16.9-20.6 years of age. One-stage closure of the soft and hard palate had been done at a mean age of 1.8 years using the Veau-Wardill-Kilner or the Cronin mucoperiosteal palatal V-Y pushback technique. The height attained in both the boys (177.6 cm) and the girls (165.7 cm) was similar to that in the general adult population, even though half of the boys had not reached their final height. The median relative weight for height and sex was 6%. There were no significant differences in dental arch measurements depending on the method of operation but the more palatal operations done the shorter the maxillary and mandibular dental arch widths. The extent of cleft made a significant difference, larger clefts having narrower palatal intercanine widths. Dental arch dimensions were consistently larger in boys than in girls.

Driven to distraction: The nature and apparent purpose of interruptions in critical care and implications for HIT.

PubMed

Mamykina, Lena; Carter, Eileen J; Sheehan, Barbara; Stanley Hum, R; Twohig, Bridget C; Kaufman, David R

2017-05-01

To examine the apparent purpose of interruptions in a Pediatric Intensive Care Unit and opportunities to reduce their burden with informatics solutions. In this prospective observational study, researchers shadowed clinicians in the unit for one hour at a time, recording all interruptions participating clinicians experienced or initiated, their starting time, duration, and a short description that could help to infer their apparent purpose. All captured interruptions were classified inductively on their source and apparent purpose and on the optimal representational media for fulfilling their apparent purpose. The researchers observed thirty-four one-hour sessions with clinicians in the unit, including 21 nurses and 13 residents and house physicians. The physicians were interrupted on average 11.9 times per hour and interrupted others 8.8 times per hour. Nurses were interrupted 8.6 times per hour and interrupted others 5.1 times per hour. The apparent purpose of interruptions included Information Seeking and Sharing (n=259, 46.3%), Directives and Requests (n=70, 12%), Shared Decision-Making (n=49, 8.8%), Direct Patient Care (n=36, 6.4%), Social (n=71, 12.7%), Device Alarms (n=28, 5%), and Non-Clinical (n=10, 1.8%); 6.6% were not classified due to insufficient description. Of all captured interruptions, 29.5% were classified as being better served with informational displays or computer-mediated communication. Deeper understanding of the purpose of interruptions in critical care can help to distinguish between interruptions that require face-to-face conversation and those that can be eliminated with informatics solutions. The proposed taxonomy of interruptions and representational analysis can be used to further advance the science of interruptions in clinical care. Copyright © 2017 Elsevier Inc. All rights reserved.

Coping with interruptions in clinical nursing-A qualitative study.

PubMed

Laustsen, Sussie; Brahe, Liselotte

2018-04-01

To gain knowledge on how nurses' cope with interruptions in clinical practice. Interruptions may delay work routines and result in wasted time, disorganised planning and ineffective working procedures, affecting nurses' focus and overview in different ways. Research has identified a growing problem linking errors or adverse events with interruptions. It may affect patient safety if nurses are not paying attention to interruptions. Little is known about how nurses cope with interruptions DESIGN: The study was inspired by ethnographic fieldwork with a hermeneutical phenomenological approach. Observations were performed combined with semi-structured qualitative interviews. Managing interruptions depend on level of competence, working environment, dialogue and matching of expectations, collegial roles and implicit rules. Working procedures impact on how nurses are exposed to unnecessary interruptions. The latter affects overview and the ability to put the foot down and decline being interrupted. Professional competencies for example prioritising, keeping focus and collaborating across disciplines are needed to cope with interruptions. Culture work and matching of expectations are important to reflect on and discuss personal- and group behaviour caused by interruptions. We need to focus on the role of each nurse in the professional team, types of personality and unspoken rules. Professional competencies for example prioritising, keeping focus and cooperating across disciplines are needed to cope with interruptions. Coping with interruptions is important for the nursing profession, quality of care and patient safety. Changing practice requires multidisciplinary cooperation accepting different agendas at personal, group and organisational levels. Nurses must understand the meaning and nature of different types of interruptions to develop coping strategies and maintain quality in care and patient safety in multidisciplinary teamwork. © 2018 John Wiley & Sons Ltd.

The Voltage Distribution Characteristics of a Hybrid Circuit Breaker During High Current Interruption

NASA Astrophysics Data System (ADS)

Cheng, Xian; Duan, Xiongying; Liao, Minfu; Huang, Zhihui; Luo, Yan; Zou, Jiyan

2013-08-01

Hybrid circuit breaker (HCB) technology based on a vacuum interrupter and a SF6 interrupter in series has become a new research direction because of the low-carbon requirements for high voltage switches. The vacuum interrupter has an excellent ability to deal with the steep rising part of the transient recovery voltage (TRV), while the SF6 interrupter can withstand the peak part of the voltage easily. An HCB can take advantage of the interrupters in the current interruption process. In this study, an HCB model based on the vacuum ion diffusion equations, ion density equation, and modified Cassie-Mayr arc equation is explored. A simulation platform is constructed by using a set of software called the alternative transient program (ATP). An HCB prototype is also designed, and the short circuit current is interrupted by the HCB under different action sequences of contacts. The voltage distribution of the HCB is analyzed through simulations and tests. The results demonstrate that if the vacuum interrupter withstands the initial TRV and interrupts the post-arc current first, then the recovery speed of the dielectric strength of the SF6 interrupter will be fast. The voltage distribution between two interrupters is determined by their post-arc resistance, which happens after current-zero, and subsequently, it is determined by the capacitive impedance after the post-arc current decays to zero.

The Effect of Interruption Duration and Demand on Resuming Suspended Goals

ERIC Educational Resources Information Center

Monk, Christopher A.; Trafton, J. Gregory; Boehm-Davis, Deborah A.

2008-01-01

The time to resume task goals after an interruption varied depending on the duration and cognitive demand of interruptions, as predicted by the memory for goals model (Altmann & Trafton, 2002). Three experiments using an interleaved tasks interruption paradigm showed that longer and more demanding interruptions led to longer resumption times in a…

Oesophageal foreign body and a double aortic arch: rare dual pathology.

PubMed

O'Connor, T E; Cooney, T

2009-12-01

We report the rare case of an oesophageal foreign body which lodged above the site of oesophageal compression by a double aortic arch. Case report and a review of the literature surrounding the classification, embryology, diagnosis and management of vascular rings and slings. An eight-month-old male infant presented with symptoms of tracheal compression following ingestion of an oesophageal foreign body. Following removal of the oesophageal foreign body, the infant's symptoms improved initially. However, subsequent recurrence of respiratory symptoms lead to a repeat bronchoscopy and the diagnosis of a coexisting double aortic arch, causing tracheal and oesophageal compression. To our knowledge, this is only the second reported case of a double aortic arch being diagnosed in a patient following removal of an oesophageal foreign body.

Effects of Aortic Irregularities on the Blood Flow

NASA Astrophysics Data System (ADS)

Gutmark-Little, Iris; Prahl-Wittberg, Lisa; van Wyk, Stevin; Mihaescu, Mihai; Fuchs, Laszlo; Backeljauw, Philippe; Gutmark, Ephraim

2013-11-01

Cardiovascular defects characterized by geometrical anomalies of the aorta and its effect on the blood flow are investigated. The flow characteristics change with the aorta geometry and the rheological properties of the blood. Flow characteristics such as wall shear stress often play an important role in the development of vascular disease. In the present study, blood is considered to be non-Newtonian and is modeled using the Quemada model, an empirical model that is valid for different red blood cell loading. Three patient-specific aortic geometries are studied using Large Eddy Simulations (LES). The three geometries represent malformations that are typical in patients populations having a genetic disorder called Turner syndrome. The results show a highly complex flow with regions of recirculation that are enhanced in two of the three aortas. Moreover, blood flow is diverted, due to the malformations, from the descending aorta to the three side branches of the arch. The geometry having an elongated transverse aorta has larger areas of strong oscillatory wall shear stress.

[Intra-operative Acute Aortic Dissection during Aortic Root Reimplantation and Mitral Valve Reconstruction Surgery in a Patient with Marfan Syndrome;Report of a Case].

PubMed

Teramoto, Chikao; Kawaguchi, Osamu; Araki, Yoshimori; Yoshikawa, Masaharu; Uchida, Wataru; Takemura, Gennta; Makino, Naoki

2016-08-01

In patients with Marfan syndrome, cardiovascular complication due to aortic dissection represents the primary cause of death. Iatrogenic acute aortic dissection during cardiac surgery is a rare, but serious adverse event. A 51-year-old woman with Marfan syndrome underwent elective aortic surgery and mitral valve reconstruction surgery for the enlarged aortic root and severe mitral regurgitation. We replaced the aortic root and ascending aorta based on reimplantation technique. During subsequent mitral valve reconstruction, we found the heart pushed up from behind. Trans-esophageal echocardiography revealed a dissecting flap in the thoracic descending aorta. There was just weak signal of blood flow in the pseudolumen. We did not add any additional procedures such as an arch replacement. Cardio-pulmonary bypass was successfully discontinued. After protamine sulfate administration and blood transfusion, blood flow in the pseudolumen disappeared. The patient was successfully discharged from the hospital on 33th postoperative day without significant morbidities.

Opioid interruptions, pain, and withdrawal symptoms in nursing home residents.

PubMed

Redding, Sarah E; Liu, Sophia; Hung, William W; Boockvar, Kenneth S

2014-11-01

Interruptions in opioid use have the potential to cause pain relapse and withdrawal symptoms. The objectives of this study were to observe patterns of opioid interruption during acute illness in nursing home residents and examine associations between interruptions and pain and withdrawal symptoms. Patients from 3 nursing homes in a metropolitan area who were prescribed opioids were assessed for symptoms of pain and withdrawal by researchers blinded to opioid dosage received, using the Brief Pain Inventory Scale and the Clinical Opioid Withdrawal Scale, respectively, during prespecified time periods. The prespecified time periods were 2 weeks after onset of acute illness (eg, urinary tract infection), and 2 weeks after hospital admission and nursing home readmission, if they occurred. Opioid dosing was recorded and a significant interruption was defined as a complete discontinuation or a reduction in dose of >50% for ≥1 day. The covariates age, sex, race, comorbid conditions, initial opioid dose, and initial pain level were recorded. Symptoms pre- and post-opioid interruptions were compared and contrasted with those in a group without opioid interruptions. Sixty-six patients receiving opioids were followed for a mean of 10.9 months and experienced a total of 104 acute illnesses. During 64 (62%) illnesses, patients experienced any reduction in opioid dosing, with a mean (SD) dose reduction of 63.9% (29.9%). During 39 (38%) illnesses, patients experienced a significant opioid interruption. In a multivariable model, residence at 1 of the 3 nursing homes was associated with a lower risk of interruption (odds ratio = 0.073; 95% CI, 0.009 to 0.597; P < 0.015). In patients with interruptions, there were statistically insignificant changes in mean (SD) pain score (difference -0.50 [2.66]; 95% CI, -3.16 to 2.16) and withdrawal score (difference -0.91 [3.12]; 95% CI, -4.03 to 2.21) after the interruption as compared with before interruption. However, when compared with patients without interruptions, patients with interruptions experienced larger increases in pain scores during the follow-up periods (difference 0.09 points per day; 95% CI, -0.01 to 0.019; P = 0.08). In particular, patients who received the highest quartile of opioid dose before interruption experienced increases in pain scores over time that were 0.22 points per day larger (95% CI, 0.02 to 0.41; P = 0.03) than those without interruption. Withdrawal scores were not associated with opioid interruption regardless of dose before interruption. Nursing home patients often experience interruptions in opioid dosing, which can be associated with worse pain, but not withdrawal symptoms, during acute illnesses. Clinicians should be aware of the potential risks and effects of opioid interruptions during acute illnesses in this patient group. Published by Elsevier Inc.

Supporting interruption management and multimodal interface design: three meta-analyses of task performance as a function of interrupting task modality.

PubMed

Lu, Sara A; Wickens, Christopher D; Prinet, Julie C; Hutchins, Shaun D; Sarter, Nadine; Sebok, Angelia

2013-08-01

The aim of this study was to integrate empirical data showing the effects of interrupting task modality on the performance of an ongoing visual-manual task and the interrupting task itself. The goal is to support interruption management and the design of multimodal interfaces. Multimodal interfaces have been proposed as a promising means to support interruption management.To ensure the effectiveness of this approach, their design needs to be based on an analysis of empirical data concerning the effectiveness of individual and redundant channels of information presentation. Three meta-analyses were conducted to contrast performance on an ongoing visual task and interrupting tasks as a function of interrupting task modality (auditory vs. tactile, auditory vs. visual, and single modality vs. redundant auditory-visual). In total, 68 studies were included and six moderator variables were considered. The main findings from the meta-analyses are that response times are faster for tactile interrupting tasks in case of low-urgency messages.Accuracy is higher with tactile interrupting tasks for low-complexity signals but higher with auditory interrupting tasks for high-complexity signals. Redundant auditory-visual combinations are preferable for communication tasks during high workload and with a small visual angle of separation. The three meta-analyses contribute to the knowledge base in multimodal information processing and design. They highlight the importance of moderator variables in predicting the effects of interruption task modality on ongoing and interrupting task performance. The findings from this research will help inform the design of multimodal interfaces in data-rich, event-driven domains.

Avoidable interruptions during drug administration in an intensive rehabilitation ward: improvement project.

PubMed

Buchini, Sara; Quattrin, Rosanna

2012-04-01

To record the frequency of interruptions and their causes, to identify 'avoidable' interruptions and to build an improvement project to reduce 'avoidable' interruptions. In Italy each year 30,000-35,000 deaths per year are attributed to health-care system errors, of which 19% are caused by medication errors. The factors that contribute to drug management error also include interruptions and carelessness during treatment administration. A descriptive study design was used to record the frequency of interruptions and their causes and to identify 'avoidable' interruptions in an intensive rehabilitation ward in Northern Italy. A data collection grid was used to record the data over a 6-month period. A total of 3000 work hours were observed. During the study period 1170 interruptions were observed. The study identified 14 causes of interruption. The study shows that of the 14 cases of interruptions at least nine can be defined as 'avoidable'. An improvement project has been proposed to reduce unnecessary interruptions and distractions to avoid making errors. An additional useful step to reduce the incidence of treatment errors would be to implement the use of a single patient medication sheet for the recording of drug prescription, preparation and administration and also the incident reporting. © 2011 Blackwell Publishing Ltd.

Dealing with task interruptions in complex dynamic environments: are two heads better than one?

PubMed

Tremblay, Sébastien; Vachon, François; Lafond, Daniel; Kramer, Chelsea

2012-02-01

This study examined whether teaming up mitigates individual vulnerability to task interruptions in complex dynamic situations. Omnipresent in everyday multitasking environments, task interruptions are usually detrimental to individual performance. This is particularly crucial in dynamic command and control (C2) safety-critical contexts because of the additional challenge imposed by the continually evolving situation during the interruption. We employed a firefighting microworld to simulate C2 in the context of supervisory control to examine the relative impact of interruptions on participants working in a functional dyad versus operators working alone. Although task interruption was detrimental to participants' efficacy of monitoring resources, the negative impact of interruption was reduced for those working in teams. Teaming up translated into faster resumption time, but only if both teammates were interrupted simultaneously. Interrupting only one team member was associated with increased postinterruption communications and slower resumption time. These findings suggest that in complex dynamic situations working in a small team confers more resistance to task interruption than working alone by virtue of the reduced individual workload typical of teamwork. The benefit of collaborative work seems nevertheless mediated by the coordination and communication overhead associated with teamwork. The present findings have practical implications for operators dealing with unexpected events such as task interruptions in C2 environments.

Design automation of load-bearing arched structures of roofs of tall buildings

NASA Astrophysics Data System (ADS)

Kulikov, Vladimir

2018-03-01

The article considers aspects of the possible use of arched roofs in the construction of skyscrapers. Tall buildings experience large load from various environmental factors. Skyscrapers are subject to various and complex types of deformation of its structural elements. The paper discusses issues related to the aerodynamics of various structural elements of tall buildings. The technique of solving systems of equations state method of Simpson. The article describes the optimization of geometric parameters of bearing elements of the arched roofs of skyscrapers.

Temporalis myofascial flap transfer into the oral cavity without zygomatic arch osteotomy

PubMed Central

Tauro, David P.; Mishra, Madan; Singh, Gaurav

2013-01-01

Among plethora of options, the temporalis myofascial flap remains a workhorse for the maxillofacial reconstruction. The inherent advantages include reliable vascularity, adequate size, and proximity to the defect. Although contemporary surgical techniques provide fair surgical results with low rate of complications, their intraoral transposition involve additional surgical trauma by intentional fracturing of the zygomatic arch. We have proposed herein a simpler technique of temporalis myofascial flap transposition into the oral cavity without zygomatic arch osteotomy. PMID:24665182

[Intraparotid first branchial arch cyst: complex diagnostic and therapeutic process].

PubMed

Gilabert Rodríguez, R; Berenguer, B; González Meli, B; Marín Molina, C; de Tomás Palacios, E; Buitrago Weiland, G; Aguado del Hoyo, A

2013-01-01

First branchial arch cysts are uncommon. Therefore, together with its variable clinical and age presentation they are often misdiagnosed at first. The treatment is surgical, requiring a correct procedure to avoid future recurrences. In this paper we describe a typical case of first branchial arch cyst in which as described in other reports, we first made several misdiagnoses and therefore an inadequate treatment and lastly, with the correct diagnosis, we performed a meticulous complete excision under facial nerve monitoring.

Integrated Design and Production Reference Integration with ArchGenXML V1.00

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barter, R H

2004-07-20

ArchGenXML is a tool that allows easy creation of Zope products through the use of Archetypes. The Integrated Design and Production Reference (IDPR) should be highly configurable in order to meet the needs of a diverse engineering community. Ease of configuration is key to the success of IDPR. The purpose of this paper is to describe a method of using a UML diagram editor to configure IDPR through ArchGenXML and Archetypes.

Complex branchial fistula: a variant arch anomaly.

PubMed

De Caluwé, D; Hayes, R; McDermott, M; Corbally, M T

2001-07-01

A 5-year-old boy presented with an infected left-sided branchial fistula. Despite antibiotic treatment and repeated excision of the fistula, purulent discharge from the wound persisted. Three-dimensional computed tomography (3D CT) reconstruction greatly facilitated the diagnosis and management of this case by showing the course of the fistulous tract. The complexity of the tract suggests that this represents a variant arch anomaly because it contains features of first, second, third, and fourth arch remnants. Copyright 2001 by W.B. Saunders Company.

A Comparison of Arch Width with Angle Classification and Wits Appraisal in Class 2 Division 1 and Class 1 Individuals.

DTIC Science & Technology

1983-05-01

longitudinal changes in arch width between lateral incisors, canines and second premolars or deciduous second molars at four stages of dental eruption in 22 male... dental arch or skeletal widths. Also, he made no attempt to divide his sample into normal and malocclusion groups. -J 7 Warren (1959) studying twenty...buccal crossbite of the posterior teeth Many clinicians believe that this problem is highly correlated with tfte type or classification of malocclusion

Analysis of Smartphone Interruptions on Academic General Internal Medicine Wards. Frequent Interruptions may cause a 'Crisis Mode' Work Climate.

PubMed

Vaisman, Alon; Wu, Robert C

2017-01-04

Hospital-based medical services are increasingly utilizing team-based pagers and smartphones to streamline communications. However, an unintended consequence may be higher volumes of interruptions potentially leading to medical error. There is likely a level at which interruptions are excessive and cause a 'crisis mode' climate. We retrospectively collected phone, text messaging, and email interruptions directed to hospital-assigned smartphones on eight General Internal Medicine (GIM) teams at two tertiary care centres in Toronto, Ontario from April 2013 to September 2014. We also calculated the number of times these interruptions exceeded a pre-specified threshold per hour, termed 'crisis mode', defined as at least five interruptions in 30 minutes. We analyzed the correlation between interruptions and date, site, and patient volumes. A total of 187,049 interruptions were collected over an 18-month period. Daily weekday interruptions rose sharply in the morning, peaking between 11 AM to 12 PM and measuring 4.8 and 3.7 mean interruptions/hour at each site, respectively. Mean daily interruptions per team totaled 46.2 ± 3.6 at Site 1 and 39.2 ± 4.2 at Site 2. The 'crisis mode' threshold was exceeded, on average, 2.3 times/day per GIM team during weekdays. In a multivariable linear regression analysis, site (β6.43 CI95% 5.44 - 7.42, p<0.001), day of the week (with Friday having the most interruptions) (β0.481 CI95% 0.236 - 0.730, p<0.05) and patient census (β1.55 CI95% 1.42 - 1.67, p<0.05) were all predictive of daily interruption volume although there was a significant interaction effect between site and patient census (β-0.941 CI95% -1.18 - -0.703, p<0.05). Interruptions were related to site-specific features, including volume, suggesting that future interventions should target the culture of individual hospitals. Excessive interruptions may have implications for patient safety especially when exceeding a maximal threshold over short periods of time.

The Effects of Career Interruptions on Young Men and Women.

ERIC Educational Resources Information Center

Shorten, Brett; Lewis, Donald E.

1991-01-01

Data from a sample of 5,837 Australians showed that (1) women had longer career interruptions; (2) regardless of number of interruptions, men had higher wages; (3) longer interruptions had a negative effect on reentry wages; and (4) 1985-88 growth in wages for males was enhanced by increased numbers and length of interruptions, with the opposite…

Fetal growth restriction: current knowledge.

PubMed

Nardozza, Luciano Marcondes Machado; Caetano, Ana Carolina Rabachini; Zamarian, Ana Cristina Perez; Mazzola, Jaqueline Brandão; Silva, Carolina Pacheco; Marçal, Vivian Macedo Gomes; Lobo, Thalita Frutuoso; Peixoto, Alberto Borges; Araujo Júnior, Edward

2017-05-01

Fetal growth restriction (FGR) is a condition that affects 5-10% of pregnancies and is the second most common cause of perinatal mortality. This review presents the most recent knowledge on FGR and focuses on the etiology, classification, prediction, diagnosis, and management of the condition, as well as on its neurological complications. The Pubmed, SCOPUS, and Embase databases were searched using the term "fetal growth restriction". Fetal growth restriction (FGR) may be classified as early or late depending on the time of diagnosis. Early FGR (<32 weeks) is associated with substantial alterations in placental implantation with elevated hypoxia, which requires cardiovascular adaptation. Perinatal morbidity and mortality rates are high. Late FGR (≥32 weeks) presents with slight deficiencies in placentation, which leads to mild hypoxia and requires little cardiovascular adaptation. Perinatal morbidity and mortality rates are lower. The diagnosis of FGR may be clinical; however, an arterial and venous Doppler ultrasound examination is essential for diagnosis and follow-up. There are currently no treatments to control FGR; the time at which pregnancy is interrupted is of vital importance for protecting both the mother and fetus. Early diagnosis of FGR is very important, because it enables the identification of the etiology of the condition and adequate monitoring of the fetal status, thereby minimizing risks of premature birth and intrauterine hypoxia.

The Epidemiology of Sleep Disordered Breathing and Hypertension in Various Populations.

PubMed

Sawatari, Hiroyuki; Chishaki, Akiko; Ando, Shin-ich

2016-01-01

Hypertension is prevalent in patients with sleep disordered breathing (SDB). Since hypertension significantly relates to cardiovascular diseases, the treatment and prevention of SDB could be targets for the prevention of cardiovascular diseases. In this article, we summarize about epidemiology of SDB and hypertension in various populations. General population based studies on the prevalence of SDB reported that 24 to 47% male and 9 to 30% female had SDB. Furthermore, the prevalence of hypertension in individuals with SDB was high, ranging from 36 to 57%. American and Korean based studies reported that the severity of SDB related to increase of blood pressure and hypertension. In the elderly, however, the severity of SDB did not relate to increase in blood pressure and hypertension, but to dipping pattern of blood pressure. With respect to children, the severity of SDB also related to increase in blood pressure, but the trend was inconstant in children with habitual snoring. In addition to the sexual differences, the severity of SDB related to hypertension in males. On the other hand, there was no relationship between the severity of SDB and hypertension in females. SDB was prevalent in the general population, regardless of race, and affected blood pressure. We should pay attention to the subjects' individual character when we interrupt the outcome.

PAs reduce rounding interruptions in the pediatric intensive care unit.

PubMed

Hascall, Rebecca L; Perkins, R Serene; Kmiecik, Lauren; Gupta, Priya R; Shelak, Carolyn F; Demirel, Shaban; Buchholz, Mark T

2018-06-01

We investigated the proportion of encounters that were interrupted during family-centered rounds in the pediatric intensive care unit (PICU) to determine whether the use of a physician assistant (PA) significantly affected the proportion of interrupted encounters. We evaluated 2,657 rounding encounters in our 24-bed regional referral unit. The duration of each rounding encounter and total rounding duration were recorded. The presence or absence of a PA during each rounding encounter, the occurrence of an interruption, and other potential predictors of interruptions were recorded. The presence of a PA during PICU rounds was significantly associated (P < .001) with a 35.4% lower likelihood of an interruption. Family-centered rounds in the PICU are less likely to be interrupted when a PA is present. PAs help physicians and improve rounding efficiency by safely and effectively handling certain interruptions.

A systematic review of the psychological literature on interruption and its patient safety implications.

PubMed

Li, Simon Y W; Magrabi, Farah; Coiera, Enrico

2012-01-01

To understand the complex effects of interruption in healthcare. As interruptions have been well studied in other domains, the authors undertook a systematic review of experimental studies in psychology and human-computer interaction to identify the task types and variables influencing interruption effects. 63 studies were identified from 812 articles retrieved by systematic searches. On the basis of interruption profiles for generic tasks, it was found that clinical tasks can be distinguished into three broad types: procedural, problem-solving, and decision-making. Twelve experimental variables that influence interruption effects were identified. Of these, six are the most important, based on the number of studies and because of their centrality to interruption effects, including working memory load, interruption position, similarity, modality, handling strategies, and practice effect. The variables are explained by three main theoretical frameworks: the activation-based goal memory model, prospective memory, and multiple resource theory. This review provides a useful starting point for a more comprehensive examination of interruptions potentially leading to an improved understanding about the impact of this phenomenon on patient safety and task efficiency. The authors provide some recommendations to counter interruption effects. The effects of interruption are the outcome of a complex set of variables and should not be considered as uniformly predictable or bad. The task types, variables, and theories should help us better to identify which clinical tasks and contexts are most susceptible and assist in the design of information systems and processes that are resilient to interruption.

22. STEEL ARCH SEGMENT AND VENT IN OFFICE, ROOM 2351, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. STEEL ARCH SEGMENT AND VENT IN OFFICE, ROOM 2351, SECOND FLOOR, NORTH SIDE. - Hughes Aircraft Company, Processing & Electronics Building, 6775 Centinela Avenue, Los Angeles, Los Angeles County, CA

3. DEADWOOD CREEK BRIDGE, VIEW BELOW DECK SHOWING OPEN SPANDREL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. DEADWOOD CREEK BRIDGE, VIEW BELOW DECK SHOWING OPEN SPANDREL ARCH CONSTRUCTION AND ARCH RIBS - Deadwood Creek Bridge, Spanning Deadwood Creek on Mather Memorial Parkway, Longmire, Pierce County, WA

Oblique view of arches and ironwork on south breezeway ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Oblique view of arches and ironwork on south breezeway - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Buildings, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

Interruptions in emergency medicine: things are not always what they seem.

PubMed

Walter, Scott R

2018-06-20

We have all felt the cognitive disjuncture of being interrupted during an important task. Most ED physicians will readily proffer the high frequency and/or burden of interruptions during their work, and of the many observational studies of interruptions in healthcare EDs do indeed have high interruption rates[2]. In experimental psychology, where many of these ideas originated, there is plenty of evidence that interruptions negatively affect performance. Interruptions have been associated with reduced performance on complex tasks[3,4], increased sequence errors[5], increased task completion time and augmented annoyance and anxiety[6]. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

An architecture for intelligent task interruption

NASA Technical Reports Server (NTRS)

Sharma, D. D.; Narayan, Srini

1990-01-01

In the design of real time systems the capability for task interruption is often considered essential. The problem of task interruption in knowledge-based domains is examined. It is proposed that task interruption can be often avoided by using appropriate functional architectures and knowledge engineering principles. Situations for which task interruption is indispensable, a preliminary architecture based on priority hierarchies is described.

Characteristics of Interruptions During Medication Administration:An Integrative Review of Direct Observational Studies.

PubMed

Schroers, Ginger

2018-06-26

The purpose of this review was to synthesize and summarize data gathered by direct observation of the characteristics of interruptions in the context of nursing medication administration in hospital settings. Interruptions are prevalent during the medication administration process performed by nurses in hospital settings and have been found to be associated with an increase in frequency and severity of nursing medication administration errors. In addition, interruptions decrease task efficiency, leading to longer medication administration completion times. Integrative review. The electronic databases Cumulative Index of Nursing and Allied Health Literature (CINAHL), PubMED, PsyARTICLES, and Google Scholar were searched using the terms "interruptions" AND "medication administration" AND "direct observation". Nine articles met the inclusion criteria. Interruptions are likely to occur at least once during nursing medication administration processes in hospital settings. This finding applies to medication administered to one patient, termed a medication pass, and medication administered to multiple patients, termed a mediation round. Interruptions are most commonly caused by another nurse, staff member, or are self-initiated, and last approximately one minute in length. A raised awareness among staff of the most common sources of interruptions may encourage changes that lead to a decrease in the occurrence of interruptions. In addition, nurse leaders can apply an understanding of the common characteristics of interruptions to guide research, policies, and educational methods aimed at interruption management strategies. The findings from this review can be used to guide the identification and development of targeted interventions and strategies that would have the most substantial impact to reduce and manage interruptions during medication administration. Interruption management strategies have the potential to lead to a decrease in medication errors and an increase in task efficiency. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

In vitro flow assessment: from PC-MRI to computational fluid dynamics including fluid-structure interaction

NASA Astrophysics Data System (ADS)

Kratzke, Jonas; Rengier, Fabian; Weis, Christian; Beller, Carsten J.; Heuveline, Vincent

2016-04-01

Initiation and development of cardiovascular diseases can be highly correlated to specific biomechanical parameters. To examine and assess biomechanical parameters, numerical simulation of cardiovascular dynamics has the potential to complement and enhance medical measurement and imaging techniques. As such, computational fluid dynamics (CFD) have shown to be suitable to evaluate blood velocity and pressure in scenarios, where vessel wall deformation plays a minor role. However, there is a need for further validation studies and the inclusion of vessel wall elasticity for morphologies being subject to large displacement. In this work, we consider a fluid-structure interaction (FSI) model including the full elasticity equation to take the deformability of aortic wall soft tissue into account. We present a numerical framework, in which either a CFD study can be performed for less deformable aortic segments or an FSI simulation for regions of large displacement such as the aortic root and arch. Both of the methods are validated by means of an aortic phantom experiment. The computational results are in good agreement with 2D phase-contrast magnetic resonance imaging (PC-MRI) velocity measurements as well as catheter-based pressure measurements. The FSI simulation shows a characteristic vessel compliance effect on the flow field induced by the elasticity of the vessel wall, which the CFD model is not capable of. The in vitro validated FSI simulation framework can enable the computation of complementary biomechanical parameters such as the stress distribution within the vessel wall.

Assessing Intracranial Vascular Compliance Using Dynamic Arterial Spin Labeling

PubMed Central

Yan, Lirong; Liu, Collin Y.; Smith, Robert X.; Jog, Mayank; Langham, Michael; Krasileva, Kate; Chen, Yufen; Ringman, John M.; Wang, Danny J.J.

2015-01-01

Vascular compliance (VC) is an important marker for a number of cardiovascular diseases and dementia, which is typically assessed in central and peripheral arteries indirectly by quantifying pulse wave velocity (PWV), and/or pulse pressure waveform. To date, very few methods are available for the quantification of intracranial VC. In the present study, a novel MRI technique for in-vivo assessment of intracranial VC was introduced, where dynamic arterial spin labeling (ASL) scans were synchronized with the systolic and diastolic phases of the cardiac cycle. VC is defined as the ratio of change in arterial cerebral blood volume (ΔCBV) and change in arterial pressure (ΔBP). Intracranial VC was assessed in different vascular components using the proposed dynamic ASL method. Our results show that VC mainly occurs in large arteries, gradually decreases in small arteries and arterioles. The comparison of intracranial VC between young and elderly subjects shows that aging is accompanied by a reduction of intracranial VC, in good agreement with the literature. Furthermore, a positive association between intracranial VC and cerebral perfusion measured using pseudo-continuous ASL with 3D GRASE MRI was observed independent of aging effects, suggesting loss of VC is associated with a decline in perfusion. Finally, a significant positive correlation between intracranial and central (aortic arch) VC was observed using an ungated phase-contrast 1D projection PWV technique. The proposed dynamic ASL method offers a promising approach for assessing intracranial VC in a range of cardiovascular diseases and dementia. PMID:26364865

[Sedation and anesthesia in dogs and cats with cardiovascular diseases. I. Anesthesia plan considering risk assessment, hemodynamic effects of drugs and monitoring].

PubMed

Skarda, R T; Bednarski, R M; Muir, W W; Hubbell, J A; Mason, D E

1995-01-01

The purpose of this study was to review the effects of sedatives and anesthetics in 137 dogs and 13 cats with congenital or acquired heart disease which were referred for diagnostic, therapeutic, and surgical interventions: correction of patent ductus arteriosus (PDA-ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral thoracotomy (8.7%), correction of right aortic arch (ring anomaly, 3.3%), correction of subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with mitral regurgitation and congestive heart failure (2%), pericardectomy and removal of heart-base tumors (2%), palliative surgery for ventricular septal defect (VSD, 0.7%), and sick patients with deleterious cardiac arrhythmias (0.7%). The anesthetic plan considered the risks of anesthesia based upon preoperative patient assessment, classification scheme for functional phases of heart failure, and anesthetic drug effects of the cardiovascular system. The effects of sedatives and anesthetic drugs on determinants of cardiac output are described. The most commonly used drugs for premedication, induction, and maintenance of anesthesia were midazolam-oxymorphone (20%), thiopental or etomidate (30%), and isoflurane (64%). Prompt therapy was given to control arrhythmias and provide organ perfusion, pain relief, muscle relaxation and renal diuresis, using lidocaine, dopamine, fentanyl, atracurium, and furosemide in 17.3% 14.7%, 12%, 10%, and 8.7% of animals, respectively. Methods of routine and advanced patient monitoring are described.

Detail view highlighting the series of pointed arch windows along ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail view highlighting the series of pointed arch windows along the North Carrollton facade - Reformed Episcopal Church of the Rock of Ages, 1210 West Lanvale Street, Baltimore, Independent City, MD

LOOKING WEST, BETWEEN READING DEPOT BRIDGE AND SKEW ARCH BRIDGE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

LOOKING WEST, BETWEEN READING DEPOT BRIDGE AND SKEW ARCH BRIDGE (HAER No. PA-116). - Philadelphia & Reading Railroad, Reading Depot Bridge, North Sixth Street at Woodward Street, Reading, Berks County, PA

1. Elkmont vehicle bridge at Elkmont Campground, galvanized corrugated arch. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Elkmont vehicle bridge at Elkmont Campground, galvanized corrugated arch. - Great Smoky Mountains National Park Roads & Bridges, Elkmont Vehicle Bridge, Spanning Little River at Elkmont Campground, Gatlinburg, Sevier County, TN

High arch

MedlinePlus

... and improve walking. This includes changes to the shoes, such as an arch insert and a support insole. Surgery to flatten the foot is sometimes needed in severe cases. Any nerve problems that exist must be treated by specialists.

5. DETAIL VIEW SHOWING ARCH AND SUPPORTS, LOOKING WESTSOUTHWEST Mike ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. DETAIL VIEW SHOWING ARCH AND SUPPORTS, LOOKING WEST-SOUTHWEST Mike Hanemann, photographer, August 1988 - Four Mile Bridge, Copper Creek Road, Spans Table Rock Fork, Mollala River, Molalla, Clackamas County, OR

5. ATTLEBORO VIADUCT: PARK STREET ARCHES. ATTLEBORO,, BRISTOL CO., MA. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. ATTLEBORO VIADUCT: PARK STREET ARCHES. ATTLEBORO,, BRISTOL CO., MA. Sec. 4116, MP 197.38. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

10. Detail view of pendant lamps, laminated arch beams and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. Detail view of pendant lamps, laminated arch beams and ceiling structure, facing north - Mountain Home Air Force Base, Base Chapel, 350 Willow Street, Cantonment Area, Mountain Home, Elmore County, ID

1. Credit JTL General view looking upstream and towards New ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Credit JTL General view looking upstream and towards New Hampshire, unidentified 'crazy man' perched on top of arch. - Bellows Falls Arch Bridge, Spanning Connecticut River, North Walpole, Cheshire County, NH

80. LITTLE ROCK DAM: DIMENSIONS, SECTION THROUGH ARCH RING, AMENDED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

80. LITTLE ROCK DAM: DIMENSIONS, SECTION THROUGH ARCH RING, AMENDED SHEET 5; SEPTEMBER, 1922. Palmdale Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. - Edwards Air Force Base, South Base Sled Track, Earth Covered Bunker Types, North of Sled Track, Lancaster, Los Angeles County, CA

3. DETAIL OF STONEWORK ON ARCH, WATER TABLE AND DENTILS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. DETAIL OF STONEWORK ON ARCH, WATER TABLE AND DENTILS ON EAST ELEVATION LOOKING NORTHWEST. - Original Airport Entrance Overpass, Spanning original Airport Entrance Road at National Airport, Arlington, Arlington County, VA

16. TAILRACE ARCH FROM 1814 MILL BROKEN THROUGH DURING EXCAVATION ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. TAILRACE ARCH FROM 1814 MILL BROKEN THROUGH DURING EXCAVATION FOR A SURFACE WATER RUNOFF POLLUTION TRAP, SUBSEQUENTLY FILLED. - Boston Manufacturing Company, 144-190 Moody Street, Waltham, Middlesex County, MA

View of south entrance to #157 through south breezeway arches ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of south entrance to #157 through south breezeway arches - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Buildings, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA