bluuebunny/crossref_metadata_2025 huggingface dataset:
Compositional and Morphological Studies of Polythiophene/Polyflorene Blends in Inverted Architecture Hybrid Solar Cells
Authors: Vaynzof Yana , Brenner Thomas J. K. , Kabra Dinesh , Sirringhaus Henning , Friend Richard H.
Published: March 2012

This work investigates the composition and morphology of films of poly(3‐hexylthiophene) (P3HT), polyfluorene co‐polymer poly((9,9‐dioctylfluorene)‐2,7‐diyl‐alt‐[4,7‐bis(3‐hexylthien‐5‐yl)‐2,1,3‐benzothiadiazole]‐2′,2″‐diyl) (F8TBT) and blends thereof that are used in efficient all‐polymer solar cells. Ultraviolet photoemission spectroscopy (UPS) and X‐ray photoemission spectroscopy (XPS) studies on thin polymer and blend films on ZnO substrates reveal the existence of a 1–2 nm thick P3HT layer at the top surface of the blend films. XPS depth profiling studies reveal a density wave (λ ≈ 70 nm) originating from the air interface. As no preferential accumulation is observed at the bottom interface with ZnO, the composition at this interface is consistent with the original composition of the blend solution prior to spin‐coating. The morphology of this buried interface was studied by means of atomic force microscopy (AFM) and revealed that upon annealing the average domain size increases slightly (from 27 nm to 40 nm). It is observed that the photovoltaic performance of such inverted hybrid device improves upon annealing, however we believe this to mostly be a result of increased crystallinity in the P3HT domains leading to improved charge transport in the device, rather than changes in the blend phase separation.
Association of shorter telomere length with essential hypertension in Indian population
Authors: Bhupatiraju Charita , Saini Divyalakshmi , Patkar Sushma , Deepak P. , Das Birajalaxmi , Padma T.
Published: March 2012

Objectives:

Essential hypertension is known to be associated with growth, development, and aging of humans. Telomeres are specialized nucleoprotein complexes consisting of tandem repeats of DNA sequences (TTAGGG)n that serve as protective caps of human chromosomes. Telomere length is considered as a biomarker of aging in somatic cells. In the present investigation, leukocyte telomere length was determined among hypertensive and normal individuals to find out the association, if any, with hypertension.

Materials and Methods:

Venous blood samples were collected from normal and hypertensive individuals with written informed consent approved by ethic committee of Department of Genetics, Osmania University Hyderabad, India. Genomic DNA was isolated from blood samples of 98 normal (age range: 30–70 years, mean age: 51.01 ± 10.12 years) and 96 hypertensive individuals (age range: 35–75 years, mean age: 49.18 ± 6.46 years). Using a SYBR green‐based real time quantitative PCR relative telomere length was determined among these individuals.

Results:

The relative telomere length (T/S ratio) in hypertensive individuals was observed to be 0.91 ± 0.16 which was significantly different (P < 0.001) from normal individuals where the relative telomere length was 0.99 ± 0.13. No significant difference was observed between relative telomere length of male and female individuals, although there is negative correlation between age and telomere length was observed in both normal and hypertensive individuals. The systolic and diastolic blood pressure was negatively correlated with relative telomere length, though not significant.

Conclusion:

Shorter telomere length is associated with hypertensive individuals in Indian population. Am. J. Hum. Biol. © 2012 Wiley Periodicals, Inc.
HBeAg(+) and sex ratio of offspring: Evidence form Taiwan's three million newborns
Authors: Lin Ming‐Jen , Chen Pei‐Jer , Luoh Ming‐Ching
Published: March 2012

Objective:

Mothers sero‐positive for hepatitis B are slightly more likely to have a son. It is not known whether it is ever having HBV (HBsAg[+]) or currently active HBV (HBeAg[+]) which is associated with having a son.

Method:

Multivariable linear regression was used to assess the adjusted association of HBeAg(+) with offspring sex in all (90%) births (∼3 million) in Taiwan from 1988 to 1999.

Results:

Totally, 5% of mothers were HBeAg(+). HBeAg(+) mothers were slightly more likely to have a son (sex ratio 108 rather than 106) adjusted for HBsAg, birth order, mother's age, birth year, and area of residence.

Conclusion:

At a population level HBV status makes little difference to the sex ratio at birth. Am. J. Hum. Biol. 2012. © 2012 Wiley Periodicals, Inc.
Evidence that nuclear factor IA inhibits repair after white matter injury
Authors: Fancy Stephen P. J. , Glasgow Stacey M. , Finley Meggie , Rowitch David H. , Deneen Benjamin
Published: March 2012

Objective:

Chronic demyelination can result in axonopathy and is associated with human neurological conditions such as multiple sclerosis (MS) in adults and cerebral palsy in infants. In these disorders, myelin regeneration is inhibited by impaired differentiation of oligodendrocyte progenitors into myelin‐producing oligodendrocytes. However, regulatory factors relevant in human myelin disorders and in myelin regeneration remain poorly understood. Here we have investigated the role of the transcription factor nuclear factor IA (NFIA) in oligodendrocyte progenitor differentiation during developmental and regenerative myelination.

Methods:

NFIA expression patterns in human neonatal hypoxic–ischemic encephalopathy (HIE) and MS as well as developmental expression in mice were evaluated. Functional studies during remyelination were performed using a lysolecithin model, coupled with lentiviral misexpression of NFIA. The role of NFIA during oligodendrocyte lineage development was characterized using chick and mouse models and in vitro culture of oligodendrocyte progenitors. Biochemical mechanism of NFIA function was evaluated using chromatin immunoprecipitation and reporter assays.

Results:

NFIA is expressed in oligodendrocyte progenitors, but not differentiated oligodendrocytes during mouse embryonic development. Examination of NFIA expression in white matter lesions of human newborns with neonatal HIE, as well active MS lesions in adults, revealed that it is similarly expressed in oligodendrocyte progenitors and not oligodendrocytes. Functional studies indicate that NFIA is sufficient to suppress oligodendrocyte progenitor differentiation during adult remyelination and embryonic development through direct repression of myelin gene expression.

Interpretation:

These studies suggest that NFIA participates in the control of oligodendrocyte progenitor differentiation and may contribute to the inhibition of remyelination in human myelin disorders. ANN NEUROL 2012;
Alternative approach to the solution of the momentum‐space Schrödinger equation for bound states of the N‐dimensional Coulomb problem
Authors: Szmytkowski R.
Published: March 2012

The Schrödinger–Coulomb problem in ℝN, N ≥ 2, is considered in the momentum representation. The adjoint Sturmian eigenvalue problem is discussed first. The resulting radial integral equation is solved with the aid of a symmetric Poisson‐type series expansion of the Legendre function of the second kind into products of the Gegenbauer polynomials, established in the 1950's by Ossicini. A relationship between solutions to the Sturmian problem and to an energy eigenvalue problem is then exploited to find the Coulomb bound‐state energy levels in ℝN, together with explicit representations of the associated momentum‐space wave functions.
Preparation and physical properties of melt‐blown nonwovens of biodegradable PLA/acetyl tributyl citrate/FePol copolyester blends
Authors: Cui Li , Zhu Chuan‐Long , Zhu Ping , Tsou Chi‐Hui , Yang Wen‐Jie , Yeh Jen‐Taut
Published: March 2012

Poly(ethylene glutaric‐co‐terephthalate) copolyester “FePol” (FP) together with a kind of citrate ester plasticizer named acetyl tributyl citrate (ATBC) were chosen to prepare PLA/FP/ATBC blends for melt blowing. Only at 250°C and 10 wt % ATBC content, those (PLAxFPy)aATBCb specimens are associated with proper rheological properties for processing melt‐blown nonwovens. As suggested by SEM, FTIR and DSC analysis, the compatible behavior between PLA and FP molecules was observed as FP content is equal to or less than 5 wt %. Further morphological analysis of (PLAxFPy)90ATBC10 specimens reveal that relatively fluffy and well‐formed nonwoven fabrics were found for (PLAxFPy)90ATBC10 nonwoven specimens melt‐blown at FP contents equal to or lower than 5 wt %. In fact, addition of FP can effectively improve tensile and burst properties of (PLAxFPy)90ATBC10 nonwovens, wherein their tensile and burst properties approach the maximum values as FP contents reach around 5 wt %. Possible reasons accounting for these melt‐blown properties of (PLAxFPy)90ATBC10 specimens are proposed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Genotoxicity of poly(propylene imine) dendrimers
Authors: Ziemba Barbara , Matuszko Gabriela , Appelhans Dietmar , Voit Brigitte , Bryszewska Maria , Klajnert Barbara
Published: March 2012

Dendrimers are highly branched macromolecules with the potential in biomedical applications. Due to positively charged surfaces, several dendrimers reveal toxicity. Coating peripheral cationic groups with carbohydrate residues can reduce it. In this study, the cytotoxicity and genotoxicity of three types of 4th generation poly(propylene imine) dendrimers were investigated. Peripheral blood mononuclear cells (PBMCs) were treated with uncoated (PPI‐g4) dendrimers, and dendrimers in which approximately 40% or 90% of peripheral amino groups were coated with maltotriose (PPI‐g4‐OS or PPI‐g4‐DS) at concentration of 0.05, 0.5, 5 mg/ml. Abbreviations OS and DS stand for open shell and dense shell respectively, that describes the structure of carbohydrate modified dendrimers. After 1 h of cell incubation at 37°C, the MTT and comet assays were performed. PPI dendrimers demonstrated surface‐modification‐degree dependent toxicity, although genotoxicity of PPI‐g4 and PPI‐g4‐OS measured by the comet assay was concentration dependent up to 0.5 mg/ml and at 5 mg/ml the amount of DNA that left comet's head decreased. Results may suggest a strong interaction between dendrimers and DNA, and furthermore, that coating PPI dendrimers by maltoriose is an efficient method to reduce their genotoxicity what opens the possibilities to use them as therapeutic agents or drug carriers. © 2012 Wiley Periodicals, Inc. Biopolymers 97: 642–648, 2012.
Potential charge transfer probe induced conformational changes of model plasma protein human serum albumin: Spectroscopic, molecular docking, and molecular dynamics simulation study
Authors: Jana Sankar , Dalapati Sasanka , Ghosh Shalini , Guchhait Nikhil
Published: March 2012

The nature of binding of specially designed charge transfer (CT) fluorophore at the hydrophobic protein interior of human serum albumin (HSA) has been explored by massive blue‐shift (82 nm) of the polarity sensitive probe emission accompanying increase in emission intensity, fluorescence anisotropy, red edge excitation shift, and average fluorescence lifetimes. Thermal unfolding of the intramolecular CT probe bound HSA produces almost opposite spectral changes. The spectral responses of the molecule reveal that it can be used as an extrinsic fluorescent reporter for similar biological systems. Circular dichrosim spectra, molecular docking, and molecular dynamics simulation studies scrutinize this binding process and stability of the protein probe complex more closely. © 2012 Wiley Periodicals, Inc. Biopolymers 97: 766–777, 2012.
Abnormal cortical sensorimotor activity during “Target” sound detection in subjects with acute acoustic trauma sequelae: an fMRI study
Authors: Job Agnès , Pons Yoann , Lamalle Laurent , Jaillard Assia , Buck Karl , Segebarth Christoph , Delon‐Martin Chantal
Published: March 2012

The most common consequences of acute acoustic trauma (AAT) are hearing loss at frequencies above 3 kHz and tinnitus. In this study, we have used functional Magnetic Resonance Imaging (fMRI) to visualize neuronal activation patterns in military adults with AAT and various tinnitus sequelae during an auditory “oddball” attention task. AAT subjects displayed overactivities principally during reflex of target sound detection, in sensorimotor areas and in emotion‐related areas such as the insula, anterior cingulate and prefrontal cortex, in premotor area, in cross‐modal sensory associative areas, and, interestingly, in a region of the Rolandic operculum that has recently been shown to be involved in tympanic movements due to air pressure. We propose further investigations of this brain area and fine middle ear investigations, because our results might suggest a model in which AAT tinnitus may arise as a proprioceptive illusion caused by abnormal excitability of middle‐ear muscle spindles possibly link with the acoustic reflex and associated with emotional and sensorimotor disturbances.
Leonardo da Vinci's “A Skull Sectioned”: Skull and dental formula revisited
Authors: Gerrits Peter O. , Veening Jan G.
Published: March 2012

What can be learned from historical anatomical drawings and how to incorporate these drawings into anatomical teaching? The drawing “A skull sectioned” (RL 19058v) by Leonardo da Vinci (1452–1519), hides more detailed information than reported earlier. A well‐chosen section cut explores sectioned paranasal sinuses and ductus nasolacrimalis. A dissected lateral wall of the maxilla is also present. Furthermore, at the level of the foramen mentale, the drawing displays compact and spongious bony components, together with a cross‐section through the foramen mentale and its connection with the canalis mandibulae. Leonardo was the first to describe a correct dental formula (6424) and made efforts to place this formula above the related dental elements. However, taking into account, the morphological features of the individual elements of the maxilla, it can be suggested that Leonardo sketched a “peculiar dental element” on the position of the right maxillary premolar in the dental sketch. The fact that the author did not make any comment on that special element is remarkable. Leonardo could have had sufficient knowledge of the precise morphology of maxillary and mandibular premolars, since the author depicted these elements in the dissected skull. The fact that the author also had access to premolars in situ corroborates our suggestion that “something went wrong” in this part of the drawing. The present study shows that historical anatomical drawings are very useful for interactive learning of detailed anatomy for students in medicine and dentistry. Clin. Anat., 2013. © 2012 Wiley Periodicals, Inc.
Sulci of the liver found after death: Their nature and potential teaching value
Authors: Macchi V. , Porzionato A. , Stecco C. , Parenti A. , Newell R.L.M. , De Caro R.
Published: March 2012

Accessory sulci of the liver are more commonly found after death than in life, raising questions as to their causation and possible classification. We have analyzed a group of 180 livers sampled from un‐embalmed (96) and embalmed cadavers (84). In un‐embalmed cadavers, no accessory sulci were found on the diaphragmatic surface in 58 cases. Diaphragmatic sulci were found in the right lobe of 38 livers. When removed from the abdominal cavity and placed flat on the examination table (the “bench position”) all 58 livers without sulci appreciable in the abdominal cavity showed the appearance of two sulci. The first ran from the right side of the inferior vena cava (IVC), curving anteriorly to the inferior border of the liver, at a point midway between the right extremity of the inferior border and the gallbladder fossa, concave towards the left. The second sulcus ran from the left side of the IVC, curving anteriorly to reach the inferior border of the liver at the level of the gallbladder fossa, concave towards the right. With progressive side‐to‐side manual compression, the sulci on the diaphragmatic surface become more evident. Division of the hepatic parenchyma along the two sulci exposed the right and middle hepatic veins respectively in more than 90% of cases. In embalmed cadavers, 24 livers showed antero‐posterior sulci in the superior surface, visible and palpable on the liver examined in situ. When the livers with sulci had been removed from the abdomen for further examination, the appearance of the superior surface did not change. In a removed liver, accessory sulci can be divided into true, “diaphragmatic,” sulci and “false” sulci due to the position of the free liver on the examination table. The “false” sulci may be considered as further morphological evidence of the functional anatomical division of the liver. Their demonstration may also be useful in teaching its topographical and surgical anatomy. Clin. Anat. 26:592–597, 2013. © 2012 Wiley Periodicals, Inc.
Musculotendinous architecture of pathological supraspinatus: A pilot in vivo ultrasonography study
Authors: Kim Soo Y. , Bleakney Robert R. , Rindlisbacher Tim , Ravichandiran Kajeandra , Rosser Benjamin W.C. , Boynton Erin
Published: March 2012

Architectural changes associated with tendon tears of the supraspinatus muscle (SP) have not been thoroughly investigated in vivo with the muscle in relaxed and contracted states. The purpose of this study was to quantify the geometric properties within the distinct regions of SP in subjects with full‐thickness tendon tears using an ultrasound protocol previously developed in our laboratory, and to compare findings with age/gender matched normal controls. Twelve SP from eight participants (6 male/2 female), mean age 57 ± 6.0 years, were investigated. Muscle geometric properties of the anterior region (middle and deep parts) and posterior region (deep part) were measured using image analysis software. Along with whole muscle thickness, fiber bundle length (FBL) and pennation angle (PA) were computed for architecturally distinct regions and/or parts. Pathologic SP was categorized according to the extent of the tear in the tendon (with or without retraction). In the anterior region, mean FBL of the pathologic SP was similar with normal controls; however, mean PA was significantly smaller in pathologic SP with retraction compared with normal controls, in the contracted state (P < 0.05). Mean FBL in the posterior region in both relaxed and contracted states was significantly shorter in the pathologic SP with retraction compared with normal controls (P < 0.05). Findings suggest FBL changes associated with tendon pathology vary between the distinct regions, and PA changes are related to whether there is retraction of the tendon. The ultrasound protocol may provide important information on architectural changes that may assist in decision making and surgical planning. Clin. Anat., 2013. © 2012 Wiley Periodicals, Inc.
Endovascular stent provides more effective early relief of SVC obstruction compared to balloon angioplasty
Authors: Aldoss Osamah , Arain Nofil , Menk Jeremiah , Kochilas Lazaros , Gruenstein Daniel
Published: March 2012

Objective

To determine whether superior vena cava (SVC) stent implantation is superior to balloon angioplasty for relieving SVC stenosis.

Background

SVC stent and balloon dilation have been used as treatment for SVC stenosis. Although safe and effective, outcome data comparing the two methods are limited.

Methods

A Pediatric Cardiac Care Consortium review identified SVC stenosis. Patients who required SVC intervention were divided into two subgroups—balloon dilation (Group A) and stent implantation (Group B). Logistic regression and the log‐rank test were used to test the need for re‐intervention within 6 months after the initial procedure.

Results

SVC intervention was performed on 210/637 patients with SVC stenosis (33%). There were 108/210 (51%) patients with balloon dilation (Group A) and 102/210 (49%) with stent implantation (Group B). Re‐intervention within 6 months of the initial intervention was more common in Group A compared to Group B [Group A = 31/40 (77.5%); Group B = 5/22 (22.7%)]. The odds‐ratio for re‐intervention within 6 months of the initial procedure for balloon vs. stent, is 7.3 [95% CI: (2.91, 22.3), P < 0.0001]. In addition, during the first 6 months after an intervention for SVC stenosis the proportion of patients with stent implantation that remained free of re‐intervention was significantly higher than after balloon angioplasty (log‐rank test, P < 0.0001). Neither age nor weight was significantly associated with the need for re‐intervention.

Conclusions

SVC stent implantation is more effective than angioplasty in relief of SVC obstruction. Weight and age are not risk factors for early re‐intervention. © 2012 Wiley Periodicals, Inc.
Acute severe mitral regurgitation following balloon mitral valvotomy: Echocardiographic features, operative findings, and outcome in 50 surgical cases
Authors: Nanjappa Manjunath C. , Ananthakrishna Rajiv , Setty Srinivasa K. Hemanna , Bhat Prabhavathi , Shankarappa Ravindranath K. , Panneerselvam Arunkumar , Kamalapurkar Giridhar , Bhat Seetharama P.S. , Rao Venugopal Ram
Published: March 2012

Objective

To analyze the echocardiographic and operative findings with respect to mitral valve anatomy in individuals undergoing emergency surgery for acute severe mitral regurgitation (MR) following balloon mitral valvotomy (BMV). In addition, the clinical profile and outcomes are highlighted.

Background

Acute severe MR is a major complication of BMV. There are only a few reports which have studied the echocardiographic and operative findings in this setting. In addition, optimal timing of surgery is uncertain.

Methods

Prospective study of 50 consecutive patients undergoing emergency mitral valve replacement (MVR) for acute severe MR following BMV.

Results

In 3855 patients who underwent BMV, acute severe MR developed in 50 cases (1.3%) and was referred for emergency MVR. Hypotension (72%), hypoxia (64%), orthopnea (14%), and pulmonary edema (12%) were the clinical manifestations. Severe MR was secondary to anterior mitral leaflet tear in 36 cases (72%), paracommisural tear with annular involvement in seven cases (14%), posterior mitral leaflet tear in five cases (10%) and chordal tear in two cases (4%). The correlation between two‐dimensional transthoracic echocardiography (2D‐TTE) and operative finding for mitral valve calcification was found to be strong (r = 0.862), in contrast to submitral fusion, where it was found to be moderate (r = 0.536). In‐hospital mortality was 12%. Mortality was higher in patients whose time to surgery was ≥24 hr when compared to those who underwent MVR within 24 hr (P < 0.001).

Conclusions

Hypotension and hypoxia are the predominant manifestations of acute severe MR following BMV. Anterior mitral leaflet tear is the most common etiology for severe MR. 2D‐TTE underestimated the severity of submitral disease. Early MVR (<24 hr) is recommended for optimal outcome. © 2012 Wiley Periodicals, Inc.
Embozene™ microspheres induced nonreperfused myocardial infarction in an experimental swine model
Authors: Varga‐Szemes Akos , Kiss Pal , Brott Brigitta C. , Wang Dezhi , Simor Tamas , Elgavish Gabriel A.
Published: March 2012

Objectives

To develop a magnetic resonance imaging (MRI) compatible, percutaneous technique for the generation of nonreperfused myocardial infarct (MI).

Background

Modeling nontreated MI has major importance in the development and preclinical testing of new therapeutic strategies for patients missing the time window suitable for revascularization following MI.

Methods

In 31 male swine, nonreperfused MI was generated by permanent occlusion of either the LAD or LCX coronary artery using 900 μm Embozene™ microspheres. Animals were monitored for 90 min postocclusion. Surviving animals were followed up for 2 (n = 6), 4 (n = 6), 14 (n = 6), or 56 (n = 6) days. At the end of the planned study session, contrast enhanced MRI, triphenyl‐tetrazolium‐chloride staining, and microscopic histopathology were carried out.

Results

The mortality rate in this study was 22.6%. Intraoperative arrhythmias occurred in 14 cases: premature ventricular complexes with (5) or without (3) ventricular tachycardia, 2nd degree atrio‐ventricular block (1), and ventricular fibrillation (6). MRI, TTC, and histology confirmed the existence of MI in every case. Macroscopic pathology showed that the microspheres caused a practically total occlusion at the epicardial level of the coronary artery. Multiple infarcts were detected in one case, probably due to unintentional reflux of the microspheres. Microspheres retained in the coronary arteries did not cause any MRI artifact.

Conclusions

The generation of nonreperfused MI is feasible by percutaneous injection of Embozene into the coronary artery system. The MI model thus obtained is suitable for the purposes of MRI experiments. © 2012 Wiley Periodicals, Inc.
Successful percutaneous transvenous antegrade mitral valve‐in‐valve implantation
Authors: Michelena Hector I. , Alli Oluseun , Cabalka Allison K. , Rihal Charanjit S.
Published: March 2012

We report a case of transcatheter valve‐in‐valve therapy performed on an 85‐year‐old man with severe mitral bioprosthetic valve dysfunction. He was a high risk candidate for conventional surgery and he underwent placement of the Melody transcatheter heart valve into the mitral bioprosthesis via the right femoral vein.© 2012 Wiley Periodicals, Inc.
Asymmetric Nucleophilic Monofluorobenzylation of Carbonyl Compounds: Synthesis of Enantiopure vic‐Fluorohydrins and α‐Fluorobenzylketones
Authors: Arroyo Yolanda , Sanz‐Tejedor M. Ascensión , Parra Alejandro , García Ruano José Luis
Published: March 2012

Asymmetric nucleophilic monofluoroalkylation of a broad range of aldehydes with an α‐fluoro‐γ‐sulfinylbenzyl carbanion takes place with complete control of the facial selectivity at the carbanion and good to high anti‐diastereoselectivity to give easily separable mixtures of two optically pure 1,2‐fluorohydrin derivatives (up to 24:1 anti/syn). Separation and removal of the p‐tolylsulfinyl group with tBuLi provides enantiomerically pure anti‐1,2‐disubstituted‐1,2‐fluorohydrins, whereas α‐fluorobenzylketones can be obtained by desulfinylation of the mixture followed by pyridinium chlorochromate oxidation (one‐pot process).
Oxygen Transport by Hemoglobin
Authors: Mairbäurl Heimo , Weber Roy E.
Published: March 2012

Hemoglobin (Hb) constitutes a vital link between ambient O2availability and aerobic metabolism by transporting oxygen (O2) from the respiratory surfaces of the lungs or gills to the O2‐consuming tissues. The amount of O2available to tissues depends on the blood‐perfusion rate, as well as the arterio‐venous difference in blood O2contents, which is determined by the respective loading and unloading O2tensions and Hb‐O2‐affinity. Short‐termadjustments in tissue oxygen delivery in response to decreased O2supply or increased O2demand (under exercise, hypoxia at high altitude, cardiovascular disease, and ischemia) are mediated by metabolically induced changes in the red cell levels of allosteric effectors such as protons (H+), carbon dioxide (CO2), organic phosphates, and chloride (Cl−) that modulate Hb‐O2affinity. Thelong‐term, genetically coded adaptations in oxygen transport encountered in animals that permanently are subjected to low environmental O2tensions commonly result from changes in the molecular structure of Hb, notably amino acid exchanges that alter Hb's intrinsic O2affinity or its sensitivity to allosteric effectors. Structure‐function studies of animal Hbs and human Hb mutants illustrate the different strategies for adjusting Hb‐O2affinity and optimizing tissue oxygen supply. © 2012 American Physiological Society.Compr Physiol2:1463‐1489, 2012.
Oxygen Uptake Kinetics
Authors: Poole David C. , Jones Andrew M.
Published: March 2012

Muscular exercise requires transitions to and from metabolic rates often exceeding an order of magnitude above resting and places prodigious demands on the oxidative machinery and O2‐transport pathway. The science of kinetics seeks to characterize the dynamic profiles of the respiratory, cardiovascular, and muscular systems and their integration to resolve the essential control mechanisms of muscle energetics and oxidative function: a goal not feasible using the steady‐state response. Essential features of the O2uptake (o2) kinetics response are highly conserved across the animal kingdom. For a given metabolic demand, fasto2kinetics mandates a smaller O2deficit, less substrate‐level phosphorylation and high exercise tolerance. By the same token, slowo2kinetics incurs a high O2deficit, presents a greater challenge to homeostasis and presages poor exercise tolerance. Compelling evidence supports that, in healthy individuals walking, running, or cycling upright,o2kinetics control resides within the exercising muscle(s) and is therefore not dependent upon, or limited by, upstream O2‐transport systems. However, disease, aging, and other imposed constraints may redistributeo2kinetics control more proximally within the O2‐transport system. Greater understanding ofo2kinetics control and, in particular, its relation to the plasticity of the O2‐transport/utilization system is considered important for improving the human condition, not just in athletic populations, but crucially for patients suffering from pathologically slowedo2kinetics as well as the burgeoning elderly population. © 2012 American Physiological Society.Compr Physiol2:933‐996, 2012.
Integration of Biological Clocks and Rhythms
Authors: Refinetti Roberto
Published: March 2012

Animals, plants, and microorganisms exhibit numerous biological rhythms that are generated by numerous biological clocks. This article summarizes experimental data pertinent to the often‐ignored issue of integration of multiple rhythms. Five contexts of integration are discussed: (i) integration of circadian rhythms of multiple processes within an individual organism, (ii) integration of biological rhythms operating in different time scales (such as tidal, daily, and seasonal), (iii) integration of rhythms across multiple species, (iv) integration of rhythms of different members of a species, and (v) integration of rhythmicity and physiological homeostasis. Understanding of these multiple rhythmic interactions is an important first step in the eventual thorough understanding of how organisms arrange their vital functions temporally within and without their bodies. © 2012 American Physiological Society.Compr Physiol2:1213‐1239, 2012.
Coordination of Breathing with Nonrespiratory Activities
Authors: Bartlett Donald , Leiter James C.
Published: March 2012

Many articles in this section ofComprehensive Physiologyare concerned with the development and function of a central pattern generator (CPG) for the control of breathing in vertebrate animals. The action of the respiratory CPG is extensively modified by cortical and other descending influences as well as by feedback from peripheral sensory systems. The central nervous system also incorporates other CPGs, which orchestrate a wide variety of discrete and repetitive, voluntary and involuntary movements. The coordination of breathing with these other activities requires interaction and coordination between the respiratory CPG and those governing the nonrespiratory activities. Most of these interactions are complex and poorly understood. They seem to involve both conventional synaptic crosstalk between groups of neurons and fluid identity of neurons as belonging to one CPG or another: neurons that normally participate in breathing may be temporarily borrowed or hijacked by a competing or interrupting activity. This review explores the control of breathing as it is influenced by many activities that are generally considered to be nonrespiratory. The mechanistic detail varies greatly among topics, reflecting the wide variety of pertinent experiments. © 2012 American Physiological Society.Compr Physiol2:1387‐1415, 2012.
The impact and outcomes of establishing an integrated interdisciplinary surgical team to care for the diabetic foot
Authors: Armstrong David G. , Bharara Manish , White Matthew , Lepow Brian , Bhatnagar Sugam , Fisher Timothy , Kimbriel Heather R. , Walters Jodi , Goshima Kaoru R. , Hughes John , Mills Joseph L.
Published: March 2012

Objective

This study aimed to quantify the impact of an integrated diabetic foot surgical service on outcomes and changes in surgical volume and focus.

Methods

We abstracted registry data from 48 consecutive months at a single institution, evaluating all patients with diabetic foot complications requiring surgery or vascular intervention, and compared outcomes in the 24 months before and after integrating podiatric surgery with vascular surgical limb‐salvage service.

Results

The service performed 2923 operations; 790 (27.0%) were related to treatment of diabetic foot complications in 374 patients. Of these, 502 were classified as non‐vascular diabetic foot surgery and 288 were vascular interventions. Urgent surgery was significantly reduced after team implementation (77.7% vs 48.5%,p < 0.0001; OR = 3.7, 95% CI: 2.4–5.5). The high/low amputation ratio decreased from 0.35 to 0.27 due to an increase in low‐level (midfoot) amputations (8.2% vs 26.1%,p < 0.0001; OR = 4.0, 95% CI: 2.0–83.3). A 45.7% reduction in below‐knee amputations was realized with a stable above‐knee/below‐knee amputation ratio (0.73–0.81). One‐third of patients required vascular intervention. Vascular reconstructions increased 44.1% following institution of the team. Initial revascularization was endovascular in 70.6% of patients. Repeat endovascular intervention or conversion to open bypass was required in 37.1% of these patients, almost double the reintervention rate of those receiving open bypass first (18.9%).

Conclusions

Interdisciplinary diabetic foot surgery teams may significantly impact surgery type, with greater focus on proactive and preventive, rather than reactive and ablative, procedures. Although endovascular limb‐sparing procedures have become increasingly applicable, open bypass remains critical to success. Copyright © 2012 John Wiley & Sons, Ltd.
Folate deficiency is associated with the formation of complex nuclear anomalies in the cytokinesis‐block micronucleus cytome assay
Authors: Bull Caroline F. , Mayrhofer Graham , Zeegers Dimphy , Mun Grace Low Kah , Hande M. Prakash , Fenech Michael F.
Published: March 2012

Chromosomal instability (CIN) is an important hallmark to oncogenesis and can be diagnosed morphologically by the presence of nuclear anomalies such as micronuclei (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBuds). We have identified additional nuclear anomalies formed under folate‐deficient conditions, defined as “fused” nuclei (FUS), “circular” nuclei (CIR), and “horse‐shoe” nuclei (HS) and investigated their suitability for inclusion as additional CIN biomarkers in the lymphocyte cytokinesis‐block micronucleus cytome (CBMN‐Cyt) assay. Although the morphological appearance of FUS, CIR, and HS suggested an origin from multiple NPB in the fusion region between the two nuclei, the very low frequency of dicentric chromosomes in metaphase spreads from these cultures did not support this model. Fluorescence in situ hybridization (FISH) analysis of cytokinesis‐blocked binucleated (BN) cells with peptide nucleic acid probes for telomeres and centromeres (PNA–FISH) revealed a high proportion of fusion regions contained both centromeric and telomeric DNA. This suggests that folate deficiency may disrupt the process of sister chromatid separation and chromosome segregation during mitosis. It was concluded that the FUS, CIR, and HS morphologies represent promising biomarkers of CIN that are sensitive to folate deficiency, and further validation and investigation of the mechanisms responsible for their formation is warranted. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc.
A computational method for geometric optimization of enhanced heat transfer devices based upon entropy generation minimization
Authors: Betchen Lee J. , Straatman Anthony G.
Published: March 2012

A computational fluid dynamics‐based optimization methodology is developed, appropriate for the geometric optimization of enhanced heat transfer devices based upon the principle of entropy generation minimization, in which the objective function is evaluated from a flow field obtained by computational simulation. A quasi‐Newton optimization procedure is employed, with computation of the objective function gradients based upon a finite difference approach. The optimization procedure is developed to be general with regard to the choice of objective function, the details of the problem under consideration, and the computational methodology employed in solving the fluid flow and heat transfer problems. A novel implementation of a Taylor series‐based procedure for the fast solution of nearby problems is presented, which is found to greatly benefit the efficiency of the present methodology. Finally, a numerical experiment is presented, illustrating the use of the present method in the geometric optimization of a practical enhanced heat transfer device on the basis of the criterion of entropy generation minimization. The optimization of the fin spacing of a simple plate fin heat sink is considered, and a comparison of the computational results with results obtained by analytical optimization based upon empirical friction factor and Nusselt number correlations is given. Copyright © 2012 John Wiley & Sons, Ltd.
Galectin‐4, a novel neuronal regulator of myelination
Authors: Stancic Mirjana , Slijepcevic Davor , Nomden Anita , Vos Michel J. , de Jonge Jenny C. , Sikkema Arend H. , Gabius Hans‐J. , Hoekstra Dick , Baron Wia
Published: March 2012

Myelination of axons by oligodendrocytes (OLGs) is essential for proper saltatory nerve conduction, i.e., rapid transmission of nerve impulses. Among others, extracellular matrix (ECM) molecules, neuronal signaling, and axonal adhesion regulate the biogenesis and maintenance of myelin membranes, driven by polarized transport of myelin‐specific proteins and lipids. Galectin‐4, a tandem‐repeat‐type lectin with affinity to sulfatide and nonsialylated termini of N‐glycans, has the ability to regulate adhesion of cells to ECM components and is also involved in polarized membrane trafficking. We, therefore, anticipated that galectin‐4 might play a role in myelination. Here, we show that in developing postnatal rat brains galectin‐4 expression is downregulated just before the onset of myelination. Intriguingly, when immature OLGs were treated with galectin‐4, OLG maturation was retarded, while a subset of the immature OLGs reverted to a morphologically less complex progenitor stage, displaying concomitantly an increase in proliferation. Similarly, myelination was inhibited when galectin‐4 or anti‐galectin‐4 antibodies were added to co‐cultures of dorsal root ganglion neurons and OLGs. Neurons and OLGs were identified as a possible source of galectin‐4, both in vitro and in vivo. In culture, neurons but not OLGs released galectin‐4. Interestingly, in co‐cultures, a reduced release of endogenous galectin‐4 correlated with the onset of myelination. Moreover, galectin‐4‐reactive sites are transiently expressed on processes of premyelinating primary OLGs, but not on neurons. Taken together, these results identify neuronal galectin‐4 as a candidate for a soluble regulator of OLG differentiation and, hence, myelination. © 2012 Wiley Periodicals, Inc.
Toll‐like receptor 4 participates in the myelin disruptions associated with chronic alcohol abuse
Authors: Alfonso‐Loeches Silvia , Pascual Maria , Gómez‐Pinedo Ulises , Pascual‐Lucas Maya , Renau‐Piqueras Jaime , Guerri Consuelo
Published: March 2012

Alcohol abuse and alcoholism can cause brain damage, loss of white matter, myelin fiber disruption, and even neuronal injury. The underlying mechanisms of these alterations remain elusive. We have shown that chronic ethanol intake, by activating glial toll‐like receptor 4 (TLR4) receptors, triggers the production of inflammatory mediators and can cause brain damage. Because neuroinflammation may be associated with demyelination and neuronal damage, we evaluate whether the ethanol‐induced TLR4‐dependent proinflammatory environment in the brain could be involved in the myelin disruptions observed in alcoholics. Using brains from wild‐type (WT) and TLR4 knockout (KO, TLR4−/−) mice, we demonstrate that chronic ethanol treatment downregulated proteins involved in myelination [proteolipid protein (PLP), myelin basic protein (MBP), myelin‐oligodendrocyte glycoprotein, 2,3‐cyclic‐nucleotide‐3‐phosphodiesterase, and myelin‐associated glycoprotein], while increased chondroitin sulfate proteoglycan NG2 (NG2)‐proteoglycan in several brain regions of ethanol‐treated WT mice. The immunohistochemistry analysis also revealed that ethanol‐treatment‐altered myelin morphology reduced the number of MBP‐positive fibers and caused oligodendrocyte death, as demonstrated by an increase in caspase‐3‐positive oligodendrocytes. The in vivo imaging system further confirmed that chronic ethanol intake markedly reduced the PLP in WT mice. Most myelin alterations were not observed in brains from ethanol‐treated TLR4−/− mice. Electron microscopy studies revealed that although 41–47% of axons showed myelin sheath disarrangements in the cerebral cortex and corpus callosum of WT ethanol‐treated mice, respectively, small focal fiber disruptions were noticed in these brain areas of ethanol‐treated TLR4−/− mice. In summary, the present results suggest that ethanol‐induced neuroinflammation might be involved in myelin disruptions and white matter loss observed in human alcoholics. © 2012 Wiley Periodicals, Inc.
Recovered alcoholics and career development: Implications for human resource development
Authors: Gedro Julie , Mercer Frances , Iodice Jody D.
Published: March 2012

This article presents three issues regarding alcoholism, recovery, and career development. First, alcoholism is a disease that creates health and wellness problems for those it afflicts. It also impacts individual and workplace productivity. Second, alcoholism has a persistent stigmatization. As a result, those alcoholics who are in recovery face challenging choices around self‐disclosure. Disclosure of one's identity as a recovering alcoholic could be perceived as risky, since it could be seen as a negative. Third, because of such risk, and because of the paucity of research within the field of human resource development around alcoholism and recovery, there is a gap in the literature regarding these issues.
Mentoring and organizational citizenship behavior: Estimating the mediating effects of organization‐based self‐esteem and affective commitment
Authors: Ghosh Rajashi , Reio Thomas G. , Haynes Ray K.
Published: March 2012

This study explored how perceptions of reciprocal support in mentoring influence mentors' and protégés' intent to extend work‐related help to coworkers in organizations. Our findings shed light on the role that organization‐based self‐esteem (OBSE) and affective organizational commitment (AOC) play as mediators in transmitting the effect of perceived reciprocal support in mentoring to mentors' and protégés' intent to engage in organizational citizenship behavior (OCB). A central premise of this study was that positive feelings of reciprocal learning and growth for mentors and protégés produce interdependence and inclinations towards organizational citizenship. Mentors (n = 82) and protégés (n = 160) from three U.S.‐based corporations were surveyed. Results of mediation analyses employing multiple mediation model testing shows statistical and practical significance for protégés' AOC and OBSE as mediators. The lack of support for any mediators for the mentors indicates that the process underlying the link between mentoring and OCB may differ for mentors and protégés. We discuss the implications of these findings for organizational mentoring and human resource development and offer suggestions for future research.
Experimental study comparing a traditional approach to performance appraisal training to a whole‐brain training method at C.B. Fleet Laboratories
Authors: Selden Sally , Sherrier Tom , Wooters Robert
Published: March 2012

The purpose of this study is to examine the effects of a new approach to performance appraisal training. Motivated by split‐brain theory and existing studies of cognitive information processing and performance appraisals, this exploratory study examined the effects of a whole‐brain approach to training managers for implementing performance appraisals. Managers at C.B. Fleet (n = 33) were randomly assigned into either the control or the experimental group. Fifty‐three employees participated in the study, with 27 employees reporting to a manager in the control group and 26 reporting to a manager in the experimental group. Managers in the control group received the company's traditional annual performance appraisal training that focused on training them to discern performance by specific dimensions, which is consistent with left‐brain activity. Managers in the experimental group received both the traditional training and training to stimulate the right brain hemisphere. The experimental training guided managers through a series of exercises to encourage them to access global impressions (person schema) of their subordinates. The effect of the experimental training was determined by surveying employees before and after the performance appraisal review cycle. The findings show that a whole‐brain approach to performance appraisal training results in positive returns from the perspective of the employees. Employees receiving performance appraisals from managers who participated in the experimental training group perceive the performance appraisal feedback and process as more useful.
Selecting the best IDF model by using the multifractal approach
Authors: García‐Marín A. P. , Ayuso‐Muñoz J. L. , Jiménez‐Hornero F. J. , Estévez J.
Published: March 2012

In this work, the multifractal properties of hourly rainfall data recorded at a location in Southern Spain have been related to the scale properties of the corresponding intensity–duration–frequency (IDF) curves. Four parametric models for the IDF curves have been fitted to the quantiles of rainfall obtained using the generalized Pareto frequency distribution function with the extreme data series obtained for the same place.

The scaling of the rainfall intensity moments has been analysed, and the empirical moments scaling exponent function has been obtained. The corresponding values ofq1andγ1have been empirical and theoretically calculated and compared with some characteristics of the different IDF models. Thus, the scaling behaviour of IDF curves has been analysed, and the best model has been selected. Copyright © 2012 John Wiley & Sons, Ltd.