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1.  Hemoglobin regulation of plant embryogenesis and plant pathogen interaction 
Plant Signaling & Behavior  2013;8(8):e25264.
Plant hemoglobins are ubiquitous molecules involved in several aspects of plant development and stress responses. Studies on the functional aspects of plant hemoglobins at the cellular level in these processes are limited, despite their ability to scavenge nitric oxide (NO), an important signal molecule interfering with hormone synthesis and sensitivity. This mini-review summarizes current knowledge on plant hemoglobins, analyzes their participation in plant pathogen interaction and embryogenesis and proposes a possible model centering on jasmonic acid (JA) as a downstream component of hemoglobin responses.
doi:10.4161/psb.25264
PMCID: PMC3999057  PMID: 23759548
hemoglobin; embryogenesis; jasmonic acid; pathogen; auxin
2.  Cognitive Strategy Use and Measured Numeric Ability in Immediate- and Long-Term Recall of Everyday Numeric Information 
PLoS ONE  2013;8(3):e57999.
The goals of this study were to assess the primary effects of the use of cognitive strategy and a combined measure of numeric ability on recall of every-day numeric information (i.e. prices). Additionally, numeric ability was assessed as a moderator in the relationship between strategy use and memory for prices. One hundred participants memorized twelve prices that varied from 1 to 6 digits; they recalled these immediately and after 7 days. The use of strategies, assessed through self-report, was associated with better overall recall, but not forgetting. Numeric ability was not associated with either better overall recall or forgetting. A small moderating interaction was found, in which higher levels of numeric ability enhanced the beneficial effects of strategy use on overall recall. Exploratory analyses found two further small moderating interactions: simple strategy use enhanced overall recall at higher levels of numeric ability, compared to complex strategy use; and complex strategy use was associated with lower levels of forgetting, but only at higher levels of numeric ability, compared to the simple strategy use. These results provide support for an objective measure of numeric ability, as well as adding to the literature on memory and the benefits of cognitive strategy use.
doi:10.1371/journal.pone.0057999
PMCID: PMC3590296  PMID: 23483964
3.  The Arabidopsis mutant, fy-1, has an ABA-insensitive germination phenotype 
Journal of Experimental Botany  2012;63(7):2693-2703.
Arabidopsis FY, a homologue of the yeast RNA 3' processing factor Pfs2p, regulates the autonomous floral transition pathway through its interaction with FCA, an RNA binding protein. It is demonstrated here that FY also influences seed dormancy. Freshly-harvested seed of the Arabidopsis fy-1 mutant germinated readily in the absence of stratification or after-ripening. Furthermore, the fy-1 mutant showed less ABA sensitivity compared with the wild type, Ler, under identical conditions. Freshly-harvested seed of fy-1 had significantly higher ABA levels than Ler, even though Ler was dormant and fy-1 germinated readily. The PPLPP domains of FY, which are required for flowering control, were not essential for the ABA-influenced repression of germination. FLC expression analysis in seeds of different genotypes suggested that the effect of FY on dormancy may not be elicited through FLC. No significant differences in CYP707A1, CYP707A2, NCED9, ABI3, and ABI4 were observed between freshly-harvested Ler and fy-1 imbibed for 48 h. GA3ox1 and GA3ox2 rapidly increased over the 48 h imbibition period for fy-1, with no significant increases in these transcripts for Ler. ABI5 levels were significantly lower in fy-1 over the 48 h imbibition period. The results suggest that FY is involved in the development of dormancy and ABA sensitivity in Arabidopsis seed.
doi:10.1093/jxb/err452
PMCID: PMC3346229  PMID: 22282534
ABA; ABI5; dormancy; flowering; FY; germination
4.  Non-symbiotic haemoglobins—What's happening beyond nitric oxide scavenging? 
AoB Plants  2012;2012:pls004.
The ating evidence suggests non-symbiotic hemoglobins affect hormone responses by scavenging NO. Auxin, jasmonic acid, salicylic acid, ethylene and abscisic acid have altered responses when hemoglobins are expressed. Non-symbiotic hemoglobin is a factor during plant development, biotic and abiotic stress.
Background and aims
Non-symbiotic haemoglobins have been an active research topic for over 30 years, during which time a considerable portfolio of knowledge has accumulated relative to their chemical and molecular properties, and their presence and mode of induction in plants. While progress has been made towards understanding their physiological role, there remain a number of unanswered questions with respect to their biological function. This review attempts to update recent progress in this area and to introduce a hypothesis as to how non-symbiotic haemoglobins might participate in regulating hormone signal transduction.
Principal results
Advances have been made towards understanding the structural nuances that explain some of the differences in ligand association characteristics of class 1 and class 2 non-symbiotic haemoglobins. Non-symbiotic haemoglobins have been found to function in seed development and germination, flowering, root development and differentiation, abiotic stress responses, pathogen invasion and symbiotic bacterial associations. Microarray analyses under various stress conditions yield uneven results relative to non-symbiotic haemoglobin expression. Increasing evidence of the role of nitric oxide (NO) in hormone responses and the known involvement of non-symbiotic haemoglobins in scavenging NO provide opportunities for fruitful research, particularly at the cellular level.
Conclusions
Circumstantial evidence suggests that non-symbiotic haemoglobins may have a critical function in the signal transduction pathways of auxin, ethylene, jasmonic acid, salicylic acid, cytokinin and abscisic acid. There is a strong need for research on haemoglobin gene expression at the cellular level relative to hormone signal transduction.
doi:10.1093/aobpla/pls004
PMCID: PMC3292739  PMID: 22479675
5.  A Procedural Approach to Remembering Personal Identification Numbers among Older Adults 
PLoS ONE  2011;6(10):e25428.
This study investigated whether a motor skill learning intervention could provide better memory for personal identification numbers (PINs) as compared to a control group. Younger (ages 18 to 40) and older (ages 61 to 92) participants were randomly assigned to conditions. All participants received three days of training consisting of 12 blocks of 12 trials each. Participants were tested immediately after training, after four days, and after seven days. Dependent measures were errors, latencies, and number of correct responses per minute. Younger participants were less error prone, faster, and produced more correct responses than older participants. Training condition (motor skill-based versus control training) had no significant effect on any of the dependent variables. Testing time had a significant effect on latency, and the effect of testing time on latency interacted with age group. In a second study, six older individuals diagnosed as having mild cognitive impairment (MCI) were trained using the motor skill learning intervention. Their performance was compared with that of the younger and older motor skill groups from the first experiment. The results showed that the older MCI group was significantly slower, more error prone, and produced fewer correct responses per minute than the older, normal group. Thus the presence of diagnosed MCI significantly impairs memory for PINs beyond the impairment expected from normal aging.
doi:10.1371/journal.pone.0025428
PMCID: PMC3187755  PMID: 21998656
6.  Plant mitochondrial function during anaerobiosis 
Annals of Botany  2008;103(2):259-268.
Background
Under hypoxic conditions, plant mitochondria preserve the capacity to oxidize external NADH, NADPH and tricarboxylic acid cycle substrates. Nitrite serves as an alternative electron acceptor at the level of cytochrome oxidase, with possibly complex III and the alternative oxidase also being involved. Nitric oxide is a significant product of the reaction, which has a high affinity for cytochrome c oxidase, inhibiting it. The excess NO is scavenged by hypoxically induced class 1 haemoglobin in the reaction involving ascorbate.
Scope
By using nitrite, mitochondria retain a limited capacity for ATP synthesis. NADH, produced from glycolysis during anaerobiosis and oxidized in the mitochondrial electron transport chain, should shift the composition of metabolites formed during anaerobiosis with increased conversion of pyruvate to alanine and greater involvement of other transamination reactions, such as those involving γ-aminobutyric acid formation.
Conclusions
Anaerobic mitochondrial metabolism may have a more significant role than previously thought in alleviating the effects of anoxia on plant cells. There is a need to re-examine mitochondrial carbon and nitrogen metabolism under anoxia to establish the extent of this involvement.
doi:10.1093/aob/mcn100
PMCID: PMC2707300  PMID: 18586697
Electron transport; haemoglobin; hypoxia; mitochondria; nitric oxide; nitrite reduction
8.  The Psychological Vital Sign: Implementation of a Computerized Psychological Distress Assessment Tool in Primary Care 
Primary healthcare providers must consider both the psychological and medical needs of their patients. Assessment of psychological distress is aided by use of a screening questionnaire. We have developed the “Psychological Vital Sign” (PVS), a computerized assessment tool based on the 10-item OQ-10 questionnaire. Initial data indicate that the system is acceptable to patients, staff and providers, and integrates well into the clinical workflow.
PMCID: PMC2232143

Results 1-8 (8)