Academic literature on the topic 'Physiological transport'

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Journal articles on the topic "Physiological transport"

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LACHENMYER, JUDI. "Physiological Aspects of Transport." International Anesthesiology Clinics 25, no. 2 (1987): 15–41. http://dx.doi.org/10.1097/00004311-198702520-00004.

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Hansford, Richard G. "Physiological role of mitochondrial Ca2+ transport." Journal of Bioenergetics and Biomembranes 26, no. 5 (October 1994): 495–508. http://dx.doi.org/10.1007/bf00762734.

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Fromm, Robert E., and R. Philip Dellinger. "Transport of Critically Ill Patients." Journal of Intensive Care Medicine 7, no. 5 (September 1992): 223–33. http://dx.doi.org/10.1177/088506669200700503.

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Critically ill patients are transported within and between hospitals on a regular basis; thus, transport of the critically ill is a component of most intensivists-practice. The motivation for these transports lies in obtaining diagnostic or therapeutic services not available at the bedside (intrahospital transport) or not available in the sending institution (interhospital transport). Deterioration in respiratory, cardiovascular, and other physiological systems is a potential complication of any patient transport. Using appropriate equipment and personnel and planning for each transport can minimize these complications and ensure optimal benefit to the patient.
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Bailey, Vickie, Kristi Cagle, Deborah Kurtz, Hala Chaaban, Dee Wu, Patricia Williams, and Edgardo Szyld. "Modern Neonatal Transport: Sound and Vibration Levels and Their Impact on Physiological Stability." American Journal of Perinatology 36, no. 04 (August 15, 2018): 352–59. http://dx.doi.org/10.1055/s-0038-1668171.

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Objective To measure sound and vibration in rotary wing air transport (RWAT) and ground ambulance transport (GAT), comparing them to current recommendations, and correlating them with physiological stability measures in transported neonates. Study Design This is a prospective cohort observational study including infants ≤ 7 days of age transported over an 8-month period. Infants with neurologic conditions were excluded. Sound and vibration was continuously measured during transport. Transport Risk Index of Physiologic Stability (TRIPS) scores were calculated from vital signs as a proxy for physiological stability. Results In total, 118 newborns were enrolled, of whom 109 were analyzed: 67 in RWAT and 42 in GAT. Peak sound levels ranged from 80.4 to 86.4 dBA in RWAT and from 70.3 to 71.6 dBA in GAT. Whole-body vibration ranged from 1.68 to 5.09 m/s2 in RWAT and from 1.82 to 3.96 m/s2 in GAT. Interval TRIPS scores for each infant were not significantly different despite excessive sound and vibration. Conclusion Noise levels during neonatal transport exceed published recommendations for both RWAT and GAT and are higher in RWAT. Transported infants are exposed to vibration levels exceeding acceptable adult standards. Despite excessive noise and vibration, levels of physiological stability remained stable after transport in both RWAT and GAT groups.
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Gunter, T. E., K. K. Gunter, S. S. Sheu, and C. E. Gavin. "Mitochondrial calcium transport: physiological and pathological relevance." American Journal of Physiology-Cell Physiology 267, no. 2 (August 1, 1994): C313—C339. http://dx.doi.org/10.1152/ajpcell.1994.267.2.c313.

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Since the initiation of work on mitochondrial Ca2+ transport in the early 1960s, the relationship between experimental observations and physiological function has often seemed enigmatic. Why, for example, should an organelle dedicated to the crucial task of producing approximately 95% of the cell's ATP sequester Ca2+, sometimes in preference to phosphorylating ADP? Why should there be two separate efflux mechanisms, the Na+ independent and the Na+ dependent, both thought until recently to be driven exclusively either directly or indirectly by the energy of the pH gradient? Does intramitochondrial free Ca2+ concentration control metabolism? Is there evidence for any separate function of the mitochondrial Ca2+ transport mechanisms under pathological conditions? What is the relationship between mitochondrial Ca2+ transport, the mitochondrial membrane permeability transition, and irreversible cell damage under pathological conditions? First, we review what is known about control of metabolism, evidence for a role for intramitochondrial Ca2+ in control of metabolism, the cellular conditions under which mitochondria are exposed to Ca2+, characteristics of the mitochondrial Ca2+ transport mechanisms including the permeability transition, and evidence for and against mitochondrial Ca2+ uptake in vivo. Then the questions listed above and others are addressed from the perspective of the characteristics of the mechanisms of mitochondrial Ca2+ transport.
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Herrera-Valdez, Marco Arieli. "A thermodynamic description for physiological transmembrane transport." F1000Research 7 (May 19, 2021): 1468. http://dx.doi.org/10.12688/f1000research.16169.3.

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A general formulation for both passive and active transmembrane transport is derived from basic thermodynamical principles. The derivation takes into account the energy required for the motion of molecules across membranes and includes the possibility of modeling asymmetric flow. Transmembrane currents can then be described by the general model in the case of electrogenic flow. As it is desirable in new models, it is possible to derive other well-known expressions for transmembrane currents as particular cases of the general formulation. For instance, the conductance-based formulation for current turns out to be a linear approximation of the general formula for current. Also, under suitable assumptions, other formulas for current based on electrodiffusion, like the constant field approximation by Goldman, can be recovered from the general formulation. The applicability of the general formulations is illustrated first with fits to existing data, and after, with models of transmembrane potential dynamics for pacemaking cardiocytes and neurons. The general formulations presented here provide a common ground for the biophysical study of physiological phenomena that depend on transmembrane transport.
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Herrera-Valdez, Marco Arieli. "A thermodynamic description for physiological transmembrane transport." F1000Research 7 (September 14, 2018): 1468. http://dx.doi.org/10.12688/f1000research.16169.1.

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A generic formulation for both passive and active transmembrane transport is derived from basic thermodynamical principles. The derivation takes into account the energy required for the motion of molecules across membranes, and includes the possibility of modeling asymmetric flow. Transmembrane currents can then be described by the generic model in the case of electrogenic flow. As it is desirable in new models, it is possible to derive other well known expressions for transmembrane currents as particular cases of the generic formulation. For instance, the conductance-based formulation for current turns out to be a linear approximation of the generic current. Also, under suitable assumptions, other formulas for current based on electrodiffusion, like the constant field approximation by Goldman, can also be recovered from the generic formulation. The applicability of the generic formulations is illustrated first with fits to existing data, and after, with models of transmembrane potential dynamics for pacemaking cardiocytes and neurons. The generic formulations presented here provide a common ground for the biophysical study of physiological phenomena that depend on transmembrane transport.
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Herrera-Valdez, Marco Arieli. "A thermodynamic description for physiological transmembrane transport." F1000Research 7 (November 21, 2018): 1468. http://dx.doi.org/10.12688/f1000research.16169.2.

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A general formulation for both passive and active transmembrane transport is derived from basic thermodynamical principles. The derivation takes into account the energy required for the motion of molecules across membranes, and includes the possibility of modeling asymmetric flow. Transmembrane currents can then be described by the general model in the case of electrogenic flow. As it is desirable in new models, it is possible to derive other well known expressions for transmembrane currents as particular cases of the general formulation. For instance, the conductance-based formulation for current turns out to be a linear approximation of the general formula for current. Also, under suitable assumptions, other formulas for current based on electrodiffusion, like the constant field approximation by Goldman, can also be recovered from the general formulation. The applicability of the general formulations is illustrated first with fits to existing data, and after, with models of transmembrane potential dynamics for pacemaking cardiocytes and neurons. The general formulations presented here provide a common ground for the biophysical study of physiological phenomena that depend on transmembrane transport.
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Hediger, M. A., and T. C. Welbourne. "Introduction: Glutamate transport, metabolism, and physiological responses." American Journal of Physiology-Renal Physiology 277, no. 4 (October 1, 1999): F477—F480. http://dx.doi.org/10.1152/ajprenal.1999.277.4.f477.

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The material covered in this set of articles was originally presented at Experimental Biology ’98, in San Francisco, CA, on April 20, 1998. Here, the participants recount important elements of current research on the role of glutamate transporter activity in cellular signaling, metabolism, and organ function. W. A. Fairman and S. G. Amara discuss the five subtypes of human excitatory amino acid transporters, with emphasis on the EAAT4 subtype. M. A. Hediger discusses the expression and action of EAAC1 subtype of the human excitatory amino acid transporter. I. Nissim provides an overview of the significant role of pH in regulating Gln/Glu metabolism in the kidney, liver, and brain. J. D. McGivan and B. Nicholson describe some characteristics of glutamate transport regulation with regard to a specific experimental model of the bovine renal epithelial cell line NBL-1. Finally, T. C. Welbourne and J. C. Matthews introduce the “functional unit” concept of glutamate transport and how this relates to both glutamine metabolism and paracellular permeability.
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DENTON, RICHARD M., and JAMES G. McCORMACK. "Physiological role of Ca2+ transport by mitochondria." Nature 315, no. 6021 (June 1985): 635. http://dx.doi.org/10.1038/315635a0.

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Dissertations / Theses on the topic "Physiological transport"

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Aiken, Simon Piers. "Physiological transport of zinc." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278677.

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Thomas, Collin Ernest. "Extracellular ATP : transport, metabolism, and physiological significance /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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Carrithers, John A. "Effects of post-exercise carbohydrate-protein feedings on muscle glycogen restoration." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1133741.

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The purpose of this investigation was to determine the effects of post-exercise carbohydrate-protein feedings on muscle glycogen restoration following exhaustive cycle ergometer exercise. Seven male collegiate cyclist (age=25.6±3.3y, ht.=180.9±8.5cm, wt.=75.4±10.7kg, VO2max=4.20±0.4 1•miri 1) performed three trials, each separated by -lwk, 1) 100% (x-D glucose (CHO), 2) 70% carbohydrate-20% protein-10% fat (CHOPRO), and 3) 86% carbohdyrate-14% amino acid (CHO-AA). All feedings were eucaloric, based upon 1.0 g•kgb.W.'1•hr"1 of carbohydrate, and administered every half hour during a four hour muscle glycogen restoration period in an 18% wt./vol. solution. Muscle biopsies were obtained immediately and four hours post exercise. Following the exhaustive exercise and every half hour for four hours a blood sample was drawn. Muscle glycogen concentrations increased 53%, 47%, and 57% for the CHO, CHO-PRO, and CHO-AA feedings, respectively, however no differences among the feedings were apparent in muscle glycogen restoration. The plasma glucose and insulin concentrations demonstrated no differences throughout the restoration period among the three feedings. These results suggest that muscle glycogen restoration does not appear to be enhanced with the addition of either protein or amino acids to an eucaloric carbohydrate feeding following an exhaustive cycle exercise. However, it appears that if adequate amounts of carbohydrates are consumed (greater than 0.70 g•kgb,W,."'•hf' carbohydrate) following exhaustive exercise, maximal muscle glycogen restoration occurs.
School of Physical Education
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Schaedler, Theresia Anna. "Molecular mechanism of transport by the secondary-active multidrug transporter LmrP." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609036.

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Wu, Linyan, and wu0071@flinders edu au. "BRAIN DERIVED NEUROTROPHIC FACTOR TRANSPORT AND PHYSIOLOGICAL SIGNIFICANCE." Flinders University. Medicine, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20071204.113001.

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Neurotrophins are important signaling molecules in neuronal survival and differentiation. The precursor forms of neurotrophins (proneurotrophins) are the dominant form of gene products in animals, which are cleaved to generate prodomain and mature neurotrophins, and are sorted to constitutive or regulated secretory pathway and released. Brain-derived neurotrophic factor (BDNF) plays a pivotal role in the brain development and in the pathogenesis of neurological diseases. In Huntington’s disease, the defective transport of BDNF in cortical and striatal neurons and the highly expressed polyQ mutant huntingtin (Htt) result in the degeneration of striatal neurons. The underlying mechanism of BDNF transport and release is remains to be investigated. Current studies were conducted to identify the mechanisms of how BDNF is transported in axons post Golgi trafficking. By using affinity purification and 2D-DIGE assay, we show Huntingtin-associated protein 1 (HAP1) interacts with the prodomain and mature BDNF. The GST pull-down assays have addressed that HAP1 directly binds to the prodomain but not to mature BDNF and this binding is decreased by PolyQ Htt. HAP1 immunoprecipitation shows that less proBDNF is associated with HAP1 in the brain homogenate of Huntington’s disease compared to the control. Co-transfections of HAP1 and BDNF plasmids in PC12 cells show HAP1 is colocalized with proBDNF and the prodomain, but not mature BDNF. ProBDNF was accumulated in the proximal and distal segments of crushed sciatic nerve in wild type mice but not in HAP1-/- mice. The activity-dependent release of the prodomain of BDNF is abolished in HAP1-/- mice. We conclude that HAP1 is the cargo-carrying molecule for proBDNF-containing vesicles and plays an essential role in the transport and release of BDNF in neuronal cells. 20-30% of people have a valine to methionine mutation at codon 66 (Val66Met) in the prodomain BDNF, which results in the retardation of transport and release of BDNF, but the mechanism is not known. Here, GST-pull down assays demonstrate that HAP1 binds Val66Met prodomain with less efficiency than the wild type and PolyQ Htt further reduced the binding, but the PC12 cells colocalization rate is almost the same between wt prodomain/HAP1 and Val66Met prodomain/HAP1, suggesting that the mutation in the prodomain may reduce the release by impairing the cargo-carrying efficiency of HAP1, but the mutation does not disrupt the sorting process. Recent studies have shown that proneurotrophins bind p75NTR and sortilin with high affinity, and trigger apoptosis of neurons in vitro. Here, we show that proBDNF plays a role in the death of axotomized sensory neurons. ProBDNF, p75NTR and sortilin are highly expressed in DRG neurons. The recombinant proBDNF induces the dose-dependent death of PC12 cells and the death activity is completely abolished in the presence of antibodies against the prodomain of BDNF. The exogenous proBDNF enhances the death of axotomized sensory neurons and the antibodies to the prodomain or exogenous sortilin-extracellular domain-Fc fusion molecule reduces the death of axotomized sensory neurons. We conclude that proBDNF induces the death of sensory neurons in neonatal rats and the suppression of endogenous proBDNF rescued the death of axotomized sensory neurons.
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Ryder, Jeffrey W. "The effects of fasting and refeeding on insulin-like growth factor-I stimulated glucose transport." Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1020146.

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Insulin-like growth factor-I (IGF-I) is a known stimulator of glucose transport. IGF binding protein 1 (IGFBP1) is a protein that regulates the actions of IGF-I by binding to IGF-I which alters it's ability to bind to the IGF-I receptor. Diet and exercise may influence this system. While IGFBP1 levels increase with fasting or prolonged exercise, feeding will reverse this elevation. The intent of this study was to determine if an in vivo manipulation of IGFBP1 affects in vitro glucose transport in the rat soleus. Sixteen male Spaque Dawley rats were fasted for 12 hours. Half of the animals were then allowed a two hour ad libitum refeeding period. Animals were anesthetized and had their soleus muscles removed. Muscles were then randomly assigned to one of four treatment groups. Treatments involved an incubation in either 4 or 8 mM glucose in either the presence or absence of IGF-I (75 ng x ml"'). Final incubation for all treatment groups included [3H]-3-O-methylglucose (437 µCi x mM-) for the measurement of glucose transport. Following incubation, muscles were weighed, homogenized in 1 ml of 10% trichloroacetic acid, and centrifuged to precipitate out protein. 100 µl of the supernatant was added to 3 ml of scintillation fluid and analyzed in a scintillation counter. Glucose transport was determined by 3H activity. A statistical analysis of the various groups shows that there is no significant difference between fasted and refed animal for any specific treatment. However, when all the fasted and refed animals area grouped, glucose transport rate is significantly greater (p<0.05) in fasted (3.59 ± 0.44 µM x ml"' x hr) animals than in refed animals (2.56 ± 0.27 µM x ml"' x hr'). Additionally, muscles that were treated with IGF-I in 8 mM glucose demonstrated a greater rate of glucose transport (5.12 ± 0.68 µM x ml-1 x hr') than all other treatments (2.13 ± 0.39 to 2.90 ± .33 µM x ml-' x hr'). This study showed that IGF-I is a stimulator of glucose transport in an 8 mM glucose media. Additionally, the results show that glucose transport is greater if the animals are fasted. The differences between fasted and refed animals demonstrated in this study supports the hypothesis that diet manipulated IGFBP1 levels are able to alter the biological effects of IGF-I.
School of Physical Education
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Mernone, Anacleto Valentino. "A mathematical study of peristaltic transport of physiological fluids." Title page, contents and summary only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phm566.pdf.

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Fortner, Stephanie A. "The effect of PAF, Lyso-PC, and Acyl-PAF on zinc diffusion and the comparison of transport mechanisms of cadmium, lead, copper, and manganese to zinc through a lipid bilayer." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1164847.

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A method was developed which allowed for more consistent liposome quality, reducing the standard error of initial rates for Zn2+ diffusion by 30%. Introducing low concentration of platelet-activating-factor (PAF), 1-palmitoyl-L-lyso-3-phosphocholine (Lyso-PC), or 1-oleoyl-2-acetyl-sn-glycero-3-phosphocholine (Acyl-PAF) to 1palmitoyl.-2-oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes did not have any noticeable impact on zinc diffusion. Since diffusion is dependent on membrane composition and properties, it can be concluded that PAF, Lyso-PC, and Acyl-PAF did not alter POPC liposome properties significantly. Zn2+ and Cd2+ kinetic experiments showed binding to the liposome surface prior to diffusion and a mutual diffusing species, the monohydroxo complex. Although Mn 2+ did not diffuse to any measurable extent, binding to the liposome surface was also observed. Cue+ and Pb 2+ on the other hand follow a more complex diffusion mechanism, which requires further investigation.
Department of Chemistry
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Xu, Fan 1960. "Effect of prolonged exercise on running economy." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68149.

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The purpose of this study was to investigate the effect of prolonged exercise on running economy. Fourteen male long distance runners performed two 90 minute runs on an outdoor 400m track at velocities equal to 65 and 80% of VO$ sb2$max. Prior to and following each 90 minute run, running economy (RE) was measured as the steady-state VO$ sb2$ during treadmill runs at speeds of 188 and 228 m/min. During the 90-min run at 65% of VO$ sb2$max, the mean weight loss was 1.3 kg. The HR was 143 bpm between minutes 5-10 and increased to 150 bpm between minutes 85-90. During the 90-min run at 80% of VO$ sb2$max, the mean weight loss was 1.4 kg. The HR was 161 bpm between minutes 5-10 and increased to 165 bpm between minutes 85-90. When the post RE test was conducted following each 90-min run, there was a significant increase in VO$ sb2$ expressed in both l/min and ml/kg$ cdot$min (a decrease in running economy). The increase in oxygen cost of running following the 90-min run at 80% of VO$ sb2$max was greater than that following the run at 65% of VO$ sb2$max.
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Deschuyteneer, Aude. "Rhesus factors: structure-function analysis and physiological role in mouse." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209354.

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Proteins of the conserved Mep-Amt-Rh superfamily, including mammalian Rhesus factors,

mediate ammonium transport. Ammonium is an important nitrogen source for the

biosynthesis of amino acids for instance but its accumulation is also known as cytotoxic in

animals. Nevertheless, the controlled disposal of ammonium in urine plays a critical role in

the regulation of the acid-base homeostasis. Alteration in ammonium transport via human Rh

proteins could have clinical outcomes. In this work, we addressed aspects of structurefunction

analysis of altered human Rhesus proteins using a heterologous expression system

and further characterized aspects of the patho-physiological roles of Rh proteins using

knockout mice models available in the laboratory.

Using a yeast-based expression assay, we characterized human Rh variants resulting from non

synonymous single nucleotide polymorphisms (nsSNPs) with known or unknown clinical

phenotypes. The HsRhAG variants (I61R, F65S) associated to overhydrated hereditary

stomatocytosis (OHSt), a disease affecting erythrocytes, proved affected in intrinsic

bidirectional ammonium transport, suggesting altered ammonium transport as a potential

hallmark of the disease. Moreover, these variants showed trans-dominant negative effects on

the activity of their native HsRhAG counterpart, suggesting altered cooperation of the

subunits in “heteromeric” transport complexes. On the other hand, we revealed that the

R202C variant of HsRhCG, the orthologue of mouse Rhcg required for optimal urinary

ammonium excretion and blood pH control, shows an impaired inherent ammonium transport

activity. HsRhCGR202C may potentially confer susceptibility to disorders leading to metabolic

acidosis for instance.

MmRhcg has been shown to be expressed in the male mice epididymal tract, its absence

leading to a more acidic luminal fluid and to a reduced male fertility. Using mice

models, we further investigated the role of Rhcg and Rhbg proteins in the male

reproductive function.


Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Books on the topic "Physiological transport"

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E, Dalbey Ross, and Heijne Gunnar von, eds. Protein targeting, transport & translocation. Amsterdam: Academic Press, 2002.

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D, Edwards J., Shoemaker William C. 1923-, and Vincent J. L, eds. Oxygen transport: Principles and practice. London: W.B. Saunders, 1993.

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W, Potts W. T., Hazon N, Eddy B, and Flik G, eds. Ionic regulation in animals: A tribute to Professor W.T.W. Potts. Berlin: Springer, 1997.

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Kasner, Scott Eric. Regulation of potassium transport in rat mesangial cells: A fluorescent analysis using the potassium sensitive dye, PBFI. [s.l: s.n.], 1992.

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Verner, Keith. Intracellular protein transport and membrane biogenesis. Austin: R.G. Landes Company, 1995.

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S, Kilberg Michael, and Häussinger D. 1951-, eds. Mammalian amino acid transport: Mechanisms and control. New York: Plenum Press, 1992.

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David, Phoenix, ed. Protein targeting and translocation. London: Portland, 1998.

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M, Seredenko M., and Instytut fiziolohiï im. O.O. Bohomolʹt͡s︡i͡a︡., eds. Mekhanizmy razvitii͡a︡ i kompensat͡s︡ii gemicheskoĭ gipoksii. Kiev: Nauk. dumka, 1987.

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Agutter, Paul S. The meaning of nucleocytoplasmic transport. New York: Chapman & Hall, 1996.

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Kosterin, S. A. Transport kalʹt͡s︡ii͡a︡ v gladkikh mysht͡s︡akh. Kiev: Nauk. dumka, 1990.

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Book chapters on the topic "Physiological transport"

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Lambers, Hans, and Rafael S. Oliveira. "Photosynthesis, Respiration, and Long-Distance Transport: Long Distance Transport of Assimilates." In Plant Physiological Ecology, 173–86. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29639-1_4.

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Lambers, Hans, F. Stuart Chapin, and Thijs L. Pons. "Long-Distance Transport of Assimilates." In Plant Physiological Ecology, 151–62. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-78341-3_4.

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Lambers, Hans, F. Stuart Chapin, and Thijs L. Pons. "Photosynthesis, Respiration, and Long-Distance Transport." In Plant Physiological Ecology, 10–153. New York, NY: Springer New York, 1998. http://dx.doi.org/10.1007/978-1-4757-2855-2_2.

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Lambers, Hans, and Rafael S. Oliveira. "Photosynthesis, Respiration, and Long-Distance Transport: Photosynthesis." In Plant Physiological Ecology, 11–114. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29639-1_2.

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Lambers, Hans, and Rafael S. Oliveira. "Photosynthesis, Respiration, and Long-Distance Transport: Respiration." In Plant Physiological Ecology, 115–72. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29639-1_3.

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Barrett, Kim E., and Lone S. Bertelsen. "Physiological Regulation of Gastrointestinal Ion Transport." In Microbial Pathogenesis and the Intestinal Epithelial Cell, 241–66. Washington, DC, USA: ASM Press, 2014. http://dx.doi.org/10.1128/9781555817848.ch14.

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Whittembury, Guillermo, and Paola Carpi-Medina. "Mechanisms of Water Transport Across Tubular Epithelia: Routes for Movement." In Advances in Physiological Research, 455–68. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4615-9492-5_25.

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Lee, Seung-Cheol, Harish Poptani, E. James Delikatny, Stephen Pickup, David S. Nelson, Stephen J. Schuster, Sunita D. Nasta, et al. "NMR Metabolic and Physiological Markers of Therapeutic Response." In Oxygen Transport to Tissue XXXII, 129–35. Boston, MA: Springer US, 2011. http://dx.doi.org/10.1007/978-1-4419-7756-4_18.

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Nałęcz, Katarzyna A., Agnieszka Wawrzeńczyk, Joanna Mroczkowska, Urszula Berent, Nilolai A. Lobanov, and Maciej J. Nałęcz. "Carnitine Transport and Physiological Function in Neurones." In Neurochemistry, 1059–64. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-5405-9_178.

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Fedosov, Sergey N. "Physiological and Molecular Aspects of Cobalamin Transport." In Subcellular Biochemistry, 347–67. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-2199-9_18.

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Conference papers on the topic "Physiological transport"

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Su, Ching Hua, Kamdeo D. Mandal, Fow-Sen Choa, Tara Carpenter, Narsingh Bahadur Singh, David Sachs, Bradley Arnold, and Brian M. Cullum. "Growth of bio sensor materials by physical vapor transport method." In Smart Biomedical and Physiological Sensor Technology XV, edited by Brian M. Cullum, Eric S. McLamore, and Douglas Kiehl. SPIE, 2018. http://dx.doi.org/10.1117/12.2303665.

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Emge, Ian, Daniel S. Kazal, Christopher Cooper, Rachit B. Sood, Sonali Saraf, Ching Hua Su, Brian M. Cullum, et al. "Optimization of sensor materials using physical vapor transport growth method." In Smart Biomedical and Physiological Sensor Technology XVIII, edited by Brian M. Cullum, Eric S. McLamore, and Douglas Kiehl. SPIE, 2021. http://dx.doi.org/10.1117/12.2586081.

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Lim, Dae Hyeong, Min Gyu Joo, Kyu Kwan Park, Jiwon Baek, Jinyi Li, and Hyoung Won Baac. "Optical design of finger-ring-based wearable healthcare devices by using Monte Carlo simulation of photon transport." In Smart Biomedical and Physiological Sensor Technology XX, edited by Brian M. Cullum, Eric S. McLamore, and Douglas Kiehl. SPIE, 2023. http://dx.doi.org/10.1117/12.2661988.

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Kaloutsakis, Georgios, Andrew Reimer, Donghwa Jeong, and Kiju Lee. "Design and Evaluation of a Multi-Sensor Unit for Measuring Physiological Stressors of Medical Transport." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-65435.

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Patients who undergo inter-hospital transfer experience increased relative mortality, ranging from 10 to 100% higher than non-transferred patients. The high-cost, increased risk of complications and poor outcomes of transferred patients warrant the critical examination of potential causes. One of the major causes may be the external stressors that patients are exposed to during medical transport. To realize simultaneous measurements of external stressors, we developed a multi-sensor unit for measuring vibration, noise, ambient temperature, and barometric pressure. For preliminary evaluation, the sensor unit was tested on 29 medical transports, 11 air transports by a helicopter and 18 ground missions by an ambulance. The average whole-body vibration for each air and ground transport was calculated at 0.3510m/s2 and 0.5871m/s2 respectively. Air transports produced much higher level of noise than the ground transports. We found no significant difference between two modes in terms of average temperature and the temperature changes. Barometric pressure drops significantly during air transport, indicating potential use of this data for automatic mode classification.
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Al-Yasari, Ali Mosa Rashid, Mohammed A. Aboktifa, Zainab Abdulkaleq Ahmed, Hadeel S. Almaliki, Ruqaya K. Abbas, and Adnan Mansour Jasim. "The physiological role of phytosomal curcumin to mitigate hemolytic anemia and cytogenic effect induced by phenylhydrazine in rats." In TRANSPORT, ECOLOGY, SUSTAINABLE DEVELOPMENT: EKO VARNA 2023. AIP Publishing, 2024. http://dx.doi.org/10.1063/5.0191865.

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Wilson, John T., Rebecca L. Dahlin, Olga Gasheva, David C. Zawieja, and James E. Moore. "Nitric Oxide Transport in Lymphatic Vessels." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53886.

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The lymphatic system plays a vital role in maintaining proper physiological function in the body. Its removal of proteins and other particulate matter from the tissue spaces is particularly important for the body’s prevention of extracellular edema [1]. After fluid is absorbed by the initial lymphatics, it is transported to lymph nodes where filtration occurs. In addition, the lymphatic system serves as a common pathway of initial metastases to regional lymph nodes for certain types of cancers [2]. Thus, the characterization of mass transport in the lymphatic system could lead to unprecedented insight into the treatment of such pathologies.
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Kroll, Keith, James B. Bassingthwaighte, and Richard B. King. "Analysis, Imaging and Visualization in Physiological Systems A MULTISUBSTRATE BLOOD-TLSSUE EXCHANGE MODEL FOR THE ANALYSIS OF TRANSIENTS IN CARDIAC TRACER." In International Symposium on Imaging in Transport Processes. Connecticut: Begellhouse, 1992. http://dx.doi.org/10.1615/ichmt.1992.intsympimgtranspproc.450.

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Tian, L., and G. Ahmadi. "Transport and Deposition of Elongated Particles in the Upper Airways." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65062.

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Transport and deposition of elongated particle and fibers have been of interest due to their pathological responses. In this work, the transport and deposition of elongated particles and ellipsoidal fibers were numerically simulated in a physiological realistic multi-level lung model. Detailed motion of the inhaled fibers and their interaction with the surrounding environment were reproduced by solving the system of coupled equations governing the elongated particles translational and rotational motions. Correlations between the deposition pattern, fiber characteristics, breathing rates, and airway morphology in human upper tracheobronchial airways were analyzed. The results were compared with experimental measurements, and good agreement was found.
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Dmitrieva, E. V., and M. A. Fesenko. "ON THE USE OF WOMEN'S LABOR IN RAILWAY TRANSPORT." In The 16th «OCCUPATION and HEALTH» Russian National Congress with International Participation (OHRNC-2021). FSBSI “IRIOH”, 2021. http://dx.doi.org/10.31089/978-5-6042929-2-1-2021-1-177-180.

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Abstract: The article discusses the issue of women's labor in the position of an assistant driver, analyzes the main harmful factors that women may encounter in the process of work. The labor intensity, in particular psycho-emotional stress and shift work, affects health, including reproductive health. The issue of conducting research within the framework of this issue is being discussed. Conclusions: The combination of unfavorable factors of the production environment and the labor process can have a harmful effect on the health (including reproductive health) of female machinists and assistant machinists. Under these conditions, the peculiarities of the functioning of the female body – increased sensitivity to the effects of harmful production factors during certain periods of the menstrual cycle require additional full-scale physiological and hygienic studies.
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Novitskaya, L. L., N. A. Galibina, Yu L. Moshchenskaya, K. M. Nikerova, T. V. Tarelkina, M. N. Podgornaya, I. N. Sofronova, and L. I. Semenova. "PHYSIOLOGICAL AND BIOCHEMICAL REACTIONS OF THE CAMBIAL REGION OF SILVER BIRCH TO DISTURBANCE OF ASSIMILATE TRANSPORT." In The All-Russian Scientific Conference with International Participation and Schools of Young Scientists "Mechanisms of resistance of plants and microorganisms to unfavorable environmental". SIPPB SB RAS, 2018. http://dx.doi.org/10.31255/978-5-94797-319-8-558-562.

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Reports on the topic "Physiological transport"

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Moran, Nava, Richard Crain, and Menahem Segal. Regulation of Ion Transport in Motor Cells of Samanea Saman by Phototransduction-Patch-Clamp, Biochemical and Physiological Approaches. United States Department of Agriculture, January 1994. http://dx.doi.org/10.32747/1994.7604299.bard.

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Philosoph-Hadas, Sonia, Peter Kaufman, Shimon Meir, and Abraham Halevy. Signal Transduction Pathway of Hormonal Action in Control and Regulation of the Gravitropic Response of Cut Flowering Stems during Storage and Transport. United States Department of Agriculture, October 1999. http://dx.doi.org/10.32747/1999.7695838.bard.

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Original objectives: The basic goal of the present project was to increase our understanding of the cellular mechanisms operating during the gravitropic response of cut flowers, for solving their bending problem without affecting flower quality. Thus, several elements operating at the 3 levels o the gravity-induced signal transduction pathway, were proposed to be examined in snapdragon stems according to the following research goals: 1) Signaling: characterize the signal transduction pathway leading to the gravitropic response, regarding the involvement of [Ca2+]cyt as a mediator of IAA movement and sensitivity to auxin. 2) Transduction by plant hormones: a) Examine the involvement of auxin in the gravitropic response of flower stems with regard to: possible participation of auxin binding protein (ABP), auxin redistribution, auxin mechanism of action (activation of H+-ATPase) mediation by changes in [Ca2+]cyt and possible regulation of auxin-induced Ca2+ action b: calmodulin-activated or Ca2+-activated protein kinases (PK). b) Examine the involvement of ethylene in the gravitropic response of flower stems with regard to auxin-induced ethylene production and sensitivity of the tissue to ethylene. 3) Response: examine the effect of gravistimulation on invertase (associated with growth and elongation) activity and invertase gene expression. 4) Commercial practice: develop practical and simple treatments to prevent bending of cut flowers grown for export. Revisions: 1) Model systems: in addition to snapdragon (Antirrhinum majus L.), 3 other model shoe systems, consisting of oat (Avena sativa) pulvini, Ornithogalun 'Nova' cut flowers and Arabidopsis thaliana inflorescence, were targeted to confirm a more general mechanism for shoot gravitropism. 2 Research topics: the involvement of ABP, auxin action, PK and invertase in the gravitropic response of snapdragon stems could not be demonstrated. Alternatively, the involvement in the gravity signaling cascade of several other physiological mediators apart of [Ca2+]cyt such as: IP3, protein phosphorylation and actin cytoskeleton, was shown. Additional topics introduced: starch statolith reorientation, differential expression of early auxin responsive genes, and differential shoot growth. Background to the topic: The gravitropic bending response of flowering shoots occurring upon their horizontal placement during shipment exhibits a major horticultural problem. In spite of extensive studies in various aboveground organs, the gravitropic response was hardly investigated in flowering shoots. Being a complex multistep process that requires the participation of various cellular components acting in succession or in parallel, analysis of the negative gravitropic response of shoot includes investigation of signal transduction elements and various regulatory physiological mediators. Major achievements: 1) A correlative role for starch statoliths as gravireceptors in flowering shoot was initially established. 2) Differentially phosphorylated proteins and IP3 levels across the oat shoe pulvini, as well as a differential appearance of 2 early auxin-responsive genes in snapdragon stems were all detected within 5-30 minutes following gravistimulation. 3) Unlike in roots, involvement of actin cytoskeleton in early events of the gravitropic response of snapdragon shoots was established. 4) An asymmetric IAA distribution, followed by an asymmetric ethylene production across snapdragon stems was found following gravistimulation. 5) The gravity-induced differential growth in shoots of snapdragon was derived from initial shrinkage of the upper stem side and a subsequent elongation o the lower stem side. 6) Shoot bending could be successfully inhibited by Ca2+ antagonists (that serve as a basis for practical treatments), kinase and phosphatase inhibitors and actin-cytoskeleton modulators. All these agents did not affect vertical growth. The essential characterization of these key events and their sequence led us to the conclusion that blocking gravity perception may be the most powerful means to inhibit bending without hampering shoot and flower growth after harvest. Implications, scientific and agriculture: The innovative results of this project have provided some new insight in the basic understanding of gravitropism in flower stalks, that partially filled the gap in our knowledge, and established useful means for its control. Additionally, our analysis has advanced the understanding of important and fundamental physiological processes involved, thereby leading to new ideas for agriculture. Gravitropism has an important impact on agriculture, particularly for controlling the bending of various important agricultural products with economic value. So far, no safe control of the undesired bending problem of flower stalks has been established. Our results show for the first time that shoot bending of cut flowers can be inhibited without adverse effects by controlling the gravity perception step with Ca2+ antagonists and cytoskeleton modulators. Such a practical benefit resulting from this project is of great economic value for the floriculture industry.
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Elliott, Jane, Maureen Muir, and Judith Green. Trajectories of everyday mobility at older age. Wellcome Centre for Cultures and Environments of Health, January 2023. http://dx.doi.org/10.58182/bnec3269.

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Background: This review and exploratory data analysis focuses on everyday mobility at older age; that is, travel outside the house for routine activities. Everyday mobility is an important determinant of health and wellbeing. Although there can be physiological reasons for declines in an individual’s capacity for mobility, trajectories are uneven. A social model of mobility at older age assumes that impairments due to bodily ageing do not inevitably lead to reduced mobility, and that policy and environmental interventions (such as transport provision, quality of built environment) can and should support mobile later lives. We scope the potential for a study of the conditions which foster trajectories of maintained or increased mobility over time, in an equitable way. Aims: With a focus on corporeal mobility in the UK (in particular England), and on social and environmental, rather than physiological factors, our aims were to: 1) scope the existing evidence on trajectories of mobility at older age; 2) assess the English Longitudinal Study of Ageing (ELSA) as a possible source of data on changes in mobility over time; 3) outline the potential for further research through identifying candidate analytical approaches and; draft an initial logic model to inform a study. Literature review findings: Literature on mobility at older age documents physiological, lifecourse, social, and environmental factors that shape trajectories of declining mobility, and the health and wellbeing consequences. There are complex and bidirectional relationships between determinants and consequences of mobility. Points of disruption in the lifecourse are points where mobility practices may change and are therefore potential points for interventions to promote greater mobility. A body of research demonstrates this through the case of concessionary bus travel for older adults in the UK, which both promotes greater mobility and appears to improve health status. There is a more mixed body of research on the environmental factors that can foster greater mobility: more research is needed on how to support mobility in place in the UK, particularly in settings outside urban centres. Compared to research on physiological factors, there is a relative dearth of evidence on population level interventions, with the exception of free bus travel. ELSA summary: The main strength of using the ELSA for understanding what influences trajectories of everyday mobility is that it is an eighteen-year longitudinal study with data collection every two years, focussing on those aged 50 and over. The sample is drawn from across England, detailed contextual information is available via linked geographical identifiers, and longitudinal and cross-sectional weights enable adjustment of the sample for non-response and attrition. The weaknesses (for studies of mobility) are the lack of fine-grained measures of ‘ability’ for many mobility indicators and the potential for reporting biases that intersect with measures of social and cultural capital. In this descriptive analysis, we document six separate measures of everyday mobility that can be derived from ELSA data, and map these to our logic model. Implications: The review identified the potential for studying the conditions for mobility at older age that could help identify and develop population level interventions. Focusing on points of disruption in the lifecourse is a potentially fruitful and tractable area of investigation. We have mapped indicators available from ELSA as a foundation for future study, and as a resource for other researchers. ELSA has some disadvantages for a study, but also many strengths. Given the complexity of causal pathways linking different conditions for maintained or increased mobility, an analysis approach directed specifically at multiple pathways (such as Qualitative Comparative Analysis) could well be fruitful."
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Blumwald, Eduardo, and Avi Sadka. Citric acid metabolism and mobilization in citrus fruit. United States Department of Agriculture, October 2007. http://dx.doi.org/10.32747/2007.7587732.bard.

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Accumulation of citric acid is a major determinant of maturity and fruit quality in citrus. Many citrus varieties accumulate citric acid in concentrations that exceed market desires, reducing grower income and consumer satisfaction. Citrate is accumulated in the vacuole of the juice sac cell, a process that requires both metabolic changes and transport across cellular membranes, in particular, the mitochondrial and the vacuolar (tonoplast) membranes. Although the accumulation of citrate in the vacuoles of juice cells has been clearly demonstrated, the mechanisms for vacuolar citrate homeostasis and the components controlling citrate metabolism and transport are still unknown. Previous results in the PIs’ laboratories have indicated that the expression of a large number of a large number of proteins is enhanced during fruit development, and that the regulation of sugar and acid content in fruits is correlated with the differential expression of a large number of proteins that could play significant roles in fruit acid accumulation and/or regulation of acid content. The objectives of this proposal are: i) the characterization of transporters that mediate the transport of citrate and determine their role in uptake/retrieval in juice sac cells; ii) the study of citric acid metabolism, in particular the effect of arsenical compounds affecting citric acid levels and mobilization; and iii) the development of a citrus fruit proteomics platform to identify and characterize key processes associated with fruit development in general and sugar and acid accumulation in particular. The understanding of the cellular processes that determine the citrate content in citrus fruits will contribute to the development of tools aimed at the enhancement of citrus fruit quality. Our efforts resulted in the identification, cloning and characterization of CsCit1 (Citrus sinensis citrate transporter 1) from Navel oranges (Citrus sinesins cv Washington). Higher levels of CsCit1 transcripts were detected at later stages of fruit development that coincided with the decrease in the juice cell citrate concentrations (Shimada et al., 2006). Our functional analysis revealed that CsCit1 mediates the vacuolar efflux of citrate and that the CsCit1 operates as an electroneutral 1CitrateH2-/2H+ symporter. Our results supported the notion that it is the low permeable citrateH2 - the anion that establishes the buffer capacity of the fruit and determines its overall acidity. On the other hand, it is the more permeable form, CitrateH2-, which is being exported into the cytosol during maturation and controls the citrate catabolism in the juice cells. Our Mass-Spectrometry-based proteomics efforts (using MALDI-TOF-TOF and LC2- MS-MS) identified a large number of fruit juice sac cell proteins and established comparisons of protein synthesis patterns during fruit development. So far, we have identified over 1,500 fruit specific proteins that play roles in sugar metabolism, citric acid cycle, signaling, transport, processing, etc., and organized these proteins into 84 known biosynthetic pathways (Katz et al. 2007). This data is now being integrated in a public database and will serve as a valuable tool for the scientific community in general and fruit scientists in particular. Using molecular, biochemical and physiological approaches we have identified factors affecting the activity of aconitase, which catalyze the first step of citrate catabolism (Shlizerman et al., 2007). Iron limitation specifically reduced the activity of the cytosolic, but not the mitochondrial, aconitase, increasing the acid level in the fruit. Citramalate (a natural compound in the juice) also inhibits the activity of aconitase, and it plays a major role in acid accumulation during the first half of fruit development. On the other hand, arsenite induced increased levels of aconitase, decreasing fruit acidity. We have initiated studies aimed at the identification of the citramalate biosynthetic pathway and the role(s) of isopropylmalate synthase in this pathway. These studies, especially those involved aconitase inhibition by citramalate, are aimed at the development of tools to control fruit acidity, particularly in those cases where acid level declines below the desired threshold. Our work has significant implications both scientifically and practically and is directly aimed at the improvement of fruit quality through the improvement of existing pre- and post-harvest fruit treatments.
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Mukkamala, Ramakrishna. Physiologic Waveform Analysis for Early Detection of Hemorrhage during Transport and Higher Echelon Medical Care of Combat Casualties. Fort Belvoir, VA: Defense Technical Information Center, March 2014. http://dx.doi.org/10.21236/ada605185.

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Tanny, Josef, Gabriel Katul, Shabtai Cohen, and Meir Teitel. Micrometeorological methods for inferring whole canopy evapotranspiration in large agricultural structures: measurements and modeling. United States Department of Agriculture, October 2015. http://dx.doi.org/10.32747/2015.7594402.bard.

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Original objectives and revisions The original objectives as stated in the approved proposal were: (1) To establish guidelines for the use of micrometeorological techniques as accurate, reliable and low-cost tools for continuous monitoring of whole canopy ET of common crops grown in large agricultural structures. (2) To adapt existing methods for protected cultivation environments. (3) To combine previously derived theoretical models of air flow and scalar fluxes in large agricultural structures (an outcome of our previous BARD project) with ET data derived from application of turbulent transport techniques for different crops and structure types. All the objectives have been successfully addressed. The study was focused on both screenhouses and naturally ventilated greenhouses, and all proposed methods were examined. Background to the topic Our previous BARD project established that the eddy covariance (EC) technique is suitable for whole canopy evapotranspiration measurements in large agricultural screenhouses. Nevertheless, the eddy covariance technique remains difficult to apply in the farm due to costs, operational complexity, and post-processing of data – thereby inviting alternative techniques to be developed. The subject of this project was: 1) the evaluation of four turbulent transport (TT) techniques, namely, Surface Renewal (SR), Flux-Variance (FV), Half-order Time Derivative (HTD) and Bowen Ratio (BR), whose instrumentation needs and operational demands are not as elaborate as the EC, to estimate evapotranspiration within large agricultural structures; and 2) the development of mathematical models able to predict water savings and account for the external environmental conditions, physiological properties of the plant, and structure properties as well as to evaluate the necessary micrometeorological conditions for utilizing the above turbulent transfer methods in such protected environments. Major conclusions and achievements The major conclusions are: (i) the SR and FV techniques were suitable for reliable estimates of ET in shading and insect-proof screenhouses; (ii) The BR technique was reliable in shading screenhouses; (iii) HTD provided reasonable results in the shading and insect proof screenhouses; (iv) Quality control analysis of the EC method showed that conditions in the shading and insect proof screenhouses were reasonable for flux measurements. However, in the plastic covered greenhouse energy balance closure was poor. Therefore, the alternative methods could not be analyzed in the greenhouse; (v) A multi-layered flux footprint model was developed for a ‘generic’ crop canopy situated within a protected environment such as a large screenhouse. The new model accounts for the vertically distributed sources and sinks within the canopy volume as well as for modifications introduced by the screen on the flow field and microenvironment. The effect of the screen on fetch as a function of its relative height above the canopy is then studied for the first time and compared to the case where the screen is absent. The model calculations agreed with field experiments based on EC measurements from two screenhouse experiments. Implications, both scientific and agricultural The study established for the first time, both experimentally and theoretically, the use of four simple TT techniques for ET estimates within large agricultural screenhouses. Such measurements, along with reliable theoretical models, will enable the future development of lowcost ET monitoring system which will be attainable for day-to-day use by growers in improving irrigation management.
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Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman, and Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580685.bard.

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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.
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Meidan, Rina, and Joy Pate. Roles of Endothelin 1 and Tumor Necrosis Factor-A in Determining Responsiveness of the Bovine Corpus Luteum to Prostaglandin F2a. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7695854.bard.

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The corpus luteum (CL) is a transient endocrine gland that has a vital role in the regulation of the estrous cycle, fertility and the maintenance of pregnancy. In the absence of appropriate support, such as occurs during maternal recognition of pregnancy, the CL will regress. Prostaglandin F2a (PGF) was first suggested as the physiological luteolysin in ruminants several decades ago. Yet, the cellular mechanisms by which PGF causes luteal regression remain poorly defined. In recent years it became evident that the process of luteal regression requires a close cooperation between steroidogenic, endothelial and immune cells, all resident cells of this gland. Changes in the population of these cells within the CL closely consort with the functional changes occurring during various stages of CL life span. The proposal aimed to gain a better understanding of the intra-ovarian regulation of luteolysis and focuses especially on the possible reasons causing the early CL (before day 5) to be refractory to the luteolytic actions of PGF. The specific aims of this proposal were to: determine if the refractoriness of the early CL to PGF is due to its inability to synthesize or respond to endothelin–1 (ET-1), determine the cellular localization of ET, PGF and tumor necrosis factor a (TNF a) receptors in early and mid luteal phases, determine the functional relationships among ET-1 and cytokines, and characterize the effects of PGF and ET-1 on prostaglandin production by luteal cell types. We found that in contrast to the mature CL, administration of PGF2a before day 5 of the bovine cycle failed to elevate ET-1, ETA receptors or to induce luteolysis. In fact, PGF₂ₐ prevented the upregulation of the ET-1 gene by ET-1 or TNFa in cultured luteal cells from day 4 CL. In addition, we reported that ECE-1 expression was elevated during the transitionof the CL from early to mid luteal phase and was accompanied by a significant rise in ET-1 peptide. This coincides with the time point at which the CL gains its responsiveness to PGF2a, suggesting that ability to synthesize ET-1 may be a prerequisite for luteolysis. We have shown that while ET-1 mRNA was exclusively localized to endothelial cells both in young and mature CL, ECE-1 was present in the endothelial cells and steroidogenic cells alike. We also found that the gene for TNF receptor I is only moderately affected by the cytokines tested, but that the gene for TNF receptor II is upregulated by ET-1 and PGF₂ₐ. However, these cytokines both increase expression of MCP-1, although TNFa is even more effective in this regard. In addition, we found that proteins involved in the transport and metabolism of PGF (PGT, PGDH, COX-2) change as the estrous cycle progresses, and could contribute to the refractoriness of young CL. The data obtained in this work illustrate ET-1 synthesis throughout the bovine cycle and provide a better understanding of the mechanisms regulating luteal regression and unravel reasons causing the CL to be refractory to PGF2a.
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Wolf, Shmuel, and William J. Lucas. Involvement of the TMV-MP in the Control of Carbon Metabolism and Partitioning in Transgenic Plants. United States Department of Agriculture, October 1999. http://dx.doi.org/10.32747/1999.7570560.bard.

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The function of the 30-kilodalton movement protein (MP) of tobacco mosaic virus (TMV) is to facilitate cell-to-cell movement of viral progeny in infected plants. Our earlier findings have indicated that this protein has a direct effect on plasmodesmal function. In addition, these studies demonstrated that constitutive expression of the TMV MP gene (under the control of the CaMV 35S promoter) in transgenic tobacco plants significantly affects carbon metabolism in source leaves and alters the biomass distribution between the various plant organs. The long-term goal of the proposed research was to better understand the factors controlling carbon translocation in plants. The specific objectives were: A) To introduce into tobacco and potato plants a virally-encoded (TMV-MP) gene that affects plasmodesmal functioning and photosynthate partitioning under tissue-specific promoters. B) To introduce into tobacco and potato plants the TMV-MP gene under the control of promoters which are tightly repressed by the Tn10-encoded Tet repressor, to enable the expression of the protein by external application of tetracycline. C) To explore the mechanism by which the TMV-MP interacts with the endogenous control o~ carbon allocation. Data obtained in our previous project together with the results of this current study established that the TMV-MP has pleiotropic effects when expressed in transgenic tobacco plants. In addition to its ability to increase the plasmodesmal size exclusion limit, it alters carbohydrate metabolism in source leaves and dry matter partitioning between the various plant organs, Expression of the TMV-MP in various tissues of transgenic potato plants indicated that sugars and starch levels in source leaves are reduced below those of control plants when the TMV-MP is expressed in green tissue only. However, when the TMV-MP was expressed predominantly in PP and CC, sugar and starch levels were raised above those of control plants. Perhaps the most significant result obtained from experiments performed on transgenic potato plants was the discovery that the influence of the TMV-MP on carbohydrate allocation within source leaves was under developmental control and was exerted only during tuber development. The complexity of the mode by which the TMV-MP exerts its effect on the process of carbohydrate allocation was further demonstrated when transgenic tobacco plants were subjected to environmental stresses such as drought stress and nutrients deficiencies, Collectively, these studies indicated that the influence of the TMV-MP on carbon allocation L the result of protein-protein interaction within the source tissue. Based on these results, together with the findings that plasmodesmata potentiate the cell-to-cell trafficking of viral and endogenous proteins and nucleoproteins complexes, we developed the theme that at the whole plant level, the phloem serves as an information superhighway. Such a long-distance communication system may utilize a new class of signaling molecules (proteins and/or RNA) to co-ordinate photosynthesis and carbon/nitrogen metabolism in source leaves with the complex growth requirements of the plant under the prevailing environmental conditions. The discovery that expression of viral MP in plants can induce precise changes in carbon metabolism and photoassimilate allocation, now provide a conceptual foundation for future studies aimed at elucidating the communication network responsible for integrating photosynthetic productivity with resource allocation at the whole-plant level. Such information will surely provide an understanding of how plants coordinate the essential physiological functions performed by distantly-separated organs. Identification of the proteins involved in mediating and controlling cell-to-cell transport, especially at the companion cell-sieve element boundary, will provide an important first step towards achieving this goal.
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10

Shani, Uri, Lynn Dudley, Alon Ben-Gal, Menachem Moshelion, and Yajun Wu. Root Conductance, Root-soil Interface Water Potential, Water and Ion Channel Function, and Tissue Expression Profile as Affected by Environmental Conditions. United States Department of Agriculture, October 2007. http://dx.doi.org/10.32747/2007.7592119.bard.

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Constraints on water resources and the environment necessitate more efficient use of water. The key to efficient management is an understanding of the physical and physiological processes occurring in the soil-root hydraulic continuum.While both soil and plant leaf water potentials are well understood, modeled and measured, the root-soil interface where actual uptake processes occur has not been sufficiently studied. The water potential at the root-soil interface (yᵣₒₒₜ), determined by environmental conditions and by soil and plant hydraulic properties, serves as a boundary value in soil and plant uptake equations. In this work, we propose to 1) refine and implement a method for measuring yᵣₒₒₜ; 2) measure yᵣₒₒₜ, water uptake and root hydraulic conductivity for wild type tomato and Arabidopsis under varied q, K⁺, Na⁺ and Cl⁻ levels in the root zone; 3) verify the role of MIPs and ion channels response to q, K⁺ and Na⁺ levels in Arabidopsis and tomato; 4) study the relationships between yᵣₒₒₜ and root hydraulic conductivity for various crops representing important botanical and agricultural species, under conditions of varying soil types, water contents and salinity; and 5) integrate the above to water uptake term(s) to be implemented in models. We have made significant progress toward establishing the efficacy of the emittensiometer and on the molecular biology studies. We have added an additional method for measuring ψᵣₒₒₜ. High-frequency water application through the water source while the plant emerges and becomes established encourages roots to develop towards and into the water source itself. The yᵣₒₒₜ and yₛₒᵢₗ values reflected wetting and drying processes in the rhizosphere and in the bulk soil. Thus, yᵣₒₒₜ can be manipulated by changing irrigation level and frequency. An important and surprising finding resulting from the current research is the obtained yᵣₒₒₜ value. The yᵣₒₒₜ measured using the three different methods: emittensiometer, micro-tensiometer and MRI imaging in both sunflower, tomato and corn plants fell in the same range and were higher by one to three orders of magnitude from the values of -600 to -15,000 cm suggested in the literature. We have added additional information on the regulation of aquaporins and transporters at the transcript and protein levels, particularly under stress. Our preliminary results show that overexpression of one aquaporin gene in tomato dramatically increases its transpiration level (unpublished results). Based on this information, we started screening mutants for other aquaporin genes. During the feasibility testing year, we identified homozygous mutants for eight aquaporin genes, including six mutants for five of the PIP2 genes. Including the homozygous mutants directly available at the ABRC seed stock center, we now have mutants for 11 of the 19 aquaporin genes of interest. Currently, we are screening mutants for other aquaporin genes and ion transporter genes. Understanding plant water uptake under stress is essential for the further advancement of molecular plant stress tolerance work as well as for efficient use of water in agriculture. Virtually all of Israel’s agriculture and about 40% of US agriculture is made possible by irrigation. Both countries face increasing risk of water shortages as urban requirements grow. Both countries will have to find methods of protecting the soil resource while conserving water resources—goals that appear to be in direct conflict. The climate-plant-soil-water system is nonlinear with many feedback mechanisms. Conceptual plant uptake and growth models and mechanism-based computer-simulation models will be valuable tools in developing irrigation regimes and methods that maximize the efficiency of agricultural water. This proposal will contribute to the development of these models by providing critical information on water extraction by the plant that will result in improved predictions of both water requirements and crop yields. Plant water use and plant response to environmental conditions cannot possibly be understood by using the tools and language of a single scientific discipline. This proposal links the disciplines of soil physics and soil physical chemistry with plant physiology and molecular biology in order to correctly treat and understand the soil-plant interface in terms of integrated comprehension. Results from the project will contribute to a mechanistic understanding of the SPAC and will inspire continued multidisciplinary research.
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