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1.
Antioxidants (Basel) ; 12(12)2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38136195

ABSTRACT

This study evaluated the impact of in vitro gastrointestinal digestion on the digestibility, amino acid release, and antioxidant activity of proteins from amaranth (Amarantus cruentus L.) and cañihua (Chenopodium pallidicaule Aellen). Antioxidant activity was assessed using ORAC, ABTS, DPPH, and cellular antioxidant activity (CAA) assays in human intestinal Caco-2 and hepatic Hep-G2 cell lines. The results showed that amaranth had higher protein digestibility (79.19%) than cañihua (71.22%). In addition, intestinal digestion promoted the release of essential amino acids, such as leucine, lysine, and phenylalanine, in both protein concentrates. Concentrations of amaranth and cañihua proteins, ranging from 0.125 to 1.0 mg mL-1, were non-cytotoxic in both cell lines. At a concentration of 0.750 mg mL-1, simulated gastrointestinal digestion enhanced cellular antioxidant activity. Intestinal digest fractions containing peptides >5 kDa were the principal contributors to CAA in both cell lines. Notably, cañihua proteins exhibited high CAA, reaching values of 85.55% and 82.57% in Caco-2 and HepG2 cells, respectively, compared to amaranth proteins, which reached 84.68% in Caco-2 and 81.06% in HepG2 cells. In conclusion, both amaranth and cañihua proteins, after simulated gastrointestinal digestion, showcased high digestibility and released peptides and amino acids with potent antioxidant properties, underscoring their potential health benefits.

2.
Behav Processes ; 205: 104820, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36646232

ABSTRACT

Throughout the last decade, the estimated global human preterm birth rate was 10.6 %, with higher rates in Asia, South America, and Africa. Preterm individuals, even in adulthood, are more likely to develop cardiorespiratory, renal, and metabolic disorders. On the other hand, when experimental animals are housed in an enriched environment during gestation, the development of the progeny in utero is accelerated, compared to standard housing conditions. By terminating gestation one and a half days before parturition, we investigated whether environmental enrichment restricted to gestation may have an impact on progeny survival. Our results demonstrate that the gestational enriched environment tripled the rat´s offspring survival, which was associated with decreased expression of anxiety-like behaviors in the pregnant mother. Sex of the offspring was not a factor in determining survival. We discuss the effect of increased secretion of various trophic factors and hormones induced by the enriched environment on progeny survival.


Subject(s)
Premature Birth , Pregnancy , Female , Infant, Newborn , Humans , Animals , Rats , Parturition
3.
Insects ; 13(11)2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36354804

ABSTRACT

The behavior of bees is modulated by the presence of other bees and potentially by the visual information transmitted by the different body positions of bees while visiting flowers. We tested whether bee body position promoted the attraction and/or antagonistic behavior of con- and hetero-specific bees that interacted on prickly pear flowers of Opuntia huajuapensis. To test this, we placed dummy model bees of Apis mellifera and the native Lithurgus littoralis in flowers in three common body positions: alert, feeding, and horizontal. The results showed that dummy model bees in feeding and horizontal body positions attracted A. mellifera bees, while the alert position attracted native male L. littoralis. Male L. littoralis bees spent more time attacking model bees in horizontal and alert positions. The position of dummy bees also influenced response times. Bees of A. mellifera responded fastest to L. littoralis in the alert and horizontal position, male L. littoralis responded fastest to con-specific bees in the alert and feeding position, and female L. littoralis responded fastest to A. mellifera bees in the feeding position. A. mellifera reacted fastest to their con-specific bees in the alert and horizontal body positions. Our results demonstrate, for the first time in bees, that the position of individuals on a floral resource provides important visual information that modulates bee behavior, and illuminates aspects that likely have implications for bees in access to floral resources.

4.
J Consult Clin Psychol ; 89(6): 537-550, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34264701

ABSTRACT

OBJECTIVE: To determine if the Transdiagnostic Intervention for Sleep and Circadian Dysfunction (TranS-C) improves functional impairment, psychiatric symptoms, and sleep and circadian functioning. METHOD: Adults diagnosed with serious mental illness (SMI) and sleep and circadian dysfunction (N = 121) were randomly allocated to TranS-C plus usual care (TranS-C + UC; n = 61; 8 individual weekly sessions) or 6 months of Usual Care followed by Delayed Treatment with TranS-C (UC-DT; n = 60). Schizophrenia (45%) and anxiety disorders (47%) were common. Blind assessments were conducted pre-treatment, post-treatment, and 6 months later (6FU). The latter two were the post-randomization points of interest. The location was Alameda County Behavioral Health Care Services (ACBHCS), a Community Mental Health Center (CMHC) in California. RESULTS: For the primary outcomes, relative to UC-DT, TranS-C + UC was associated with reduction in functional impairment (b = -3.18, p = 0.025, d = -0.58), general psychiatric symptoms (b = -5.88, p = 0.001, d = -0.64), sleep disturbance (b = -5.55, p < .0001, d = -0.96), and sleep-related impairment (b = -9.14, p < .0001, d = -0.81) from pre-treatment to post-treatment. These effects were maintained to 6-month follow-up (6FU; d = -0.42 to -0.82), except functional impairment (d = -0.37). For the secondary outcomes, relative to UC-DT, TranS-C + UC was associated with improvement in sleep efficiency and on the Sleep Health Composite score from pre-treatment to 6FU. TranS-C + UC was also associated with reduced total wake time and wake time variability from pre-treatment to post-treatment, as well as reduced hallucinations and delusions, bedtime variability, and actigraphy measured waking activity count variability from pre-treatment to 6FU. CONCLUSIONS: A novel transdiagnostic treatment, delivered within a CMHC setting, improves selected measures of functioning, symptoms of comorbid disorders, and sleep and circadian outcomes. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Subject(s)
Community Mental Health Centers , Mental Disorders/therapy , Psychotherapy/methods , Sleep Disorders, Circadian Rhythm/therapy , Sleep Wake Disorders/therapy , Adult , Anxiety/therapy , Anxiety Disorders/therapy , California , Female , Humans , Male , Mental Disorders/complications , Middle Aged , Schizophrenia/therapy , Sleep , Sleep Disorders, Circadian Rhythm/complications , Sleep Wake Disorders/complications , Treatment Outcome
5.
J Child Psychol Psychiatry ; 61(6): 653-661, 2020 06.
Article in English | MEDLINE | ID: mdl-31773734

ABSTRACT

BACKGROUND: This study examined the 6-month follow-up outcomes of the Transdiagnostic Sleep and Circadian Intervention (TranS-C), compared to Psychoeducation about sleep and health (PE). METHODS: Adolescents (mean [SD] = 14.77 [1.84] years) with eveningness chronotype and "at-risk" in at least one of five health domains were randomized to receive TranS-C (n = 89) or PE (n = 87) at a university-based clinic. Primary outcomes were average weeknight total sleep time and bedtime calculated from sleep diary, a questionnaire measure of circadian preference, and composite risks in five health domains. Secondary outcomes were selected sleep diary indices, sleepiness, and self- and parent-reported sleep, parent-reported risks in five health domains. RESULTS: Relative to PE, TranS-C showed treatment effects through 6-month follow-up on only one primary outcome; namely eveningness circadian preference. TranS-C also showed treatment effects on two sleep and circadian secondary outcomes, including the Pittsburgh Sleep Quality Index and sleep-diary measured weeknight-weekend discrepancy in wakeup time. TranS-C did not show treatment effects on self-report or parent-report composite risks in five health domains. PE showed benefit, relative to TranS-C, from posttreatment to 6-month follow-up for reducing parent-reported behavioral health risk (secondary outcome). CONCLUSIONS: In at-risk adolescents, the evidence supports the TranS-C treatment effects over six months on improving sleep and circadian functioning on selected outcomes but not on reducing risk in five health domains.


Subject(s)
Circadian Rhythm , Sleep Wake Disorders/therapy , Sleep , Adolescent , Female , Follow-Up Studies , Humans , Male , Self Report , Time Factors
6.
J Consult Clin Psychol ; 87(9): 757-771, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31246052

ABSTRACT

OBJECTIVE: The present study tested whether improvements in sleep and circadian problems mediate the effect of a novel transdiagnostic sleep and circadian intervention (TranS-C) on improvements in 5 health domains (emotional, cognitive, behavioral, social, and physical) in community-residing, evening chronotype adolescents who were at risk for problems in these 5 health domains. METHOD: Participants were 176 adolescents (age mean [SD] = 14.77 [1.84] years; 58% female) who were randomized to receive 6 sessions of TranS-C or psychoeducation. Putative mediators tested were eveningness, weekday-weekend discrepancy in total sleep time and waketime, daytime sleepiness, Pittsburgh Sleep Quality Index score, and parent-reported sleep-wake problems. Risk in 5 health domains was measured using adolescent self-reported questionnaires, parent-reported Child Behavior Checklist, and ecological momentary assessment (EMA) of problems in the 5 health domains. RESULTS: Reduced eveningness mediated the effects of TranS-C on reducing both self-reported and parent-reported risk in the 5 health domains. Reduction in daytime sleepiness mediated the effects of TranS-C on parent-reported risk in the 5 health domains. Reduction in parent-reported sleep-wake problems mediated the effects of TranS-C on self-reported, parent-reported, and EMA-assessed risk in the 5 health domains. Results did not support the other hypothesized mediators. CONCLUSIONS: TranS-C exerts effects on reducing risk in multiple mental and physical health domains through reducing sleep and circadian problems in evening chronotype adolescents. Further research of TranS-C in other samples to assess its benefits for sleep and circadian problems as well as mental and physical health is warranted. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Subject(s)
Chronotherapy/methods , Circadian Rhythm/physiology , Motivational Interviewing/methods , Psychotherapy/methods , Sleep Wake Disorders/therapy , Sleep/physiology , Sleepiness , Adolescent , Child , Female , Humans , Male , Patient Education as Topic/methods , Treatment Outcome
7.
Sleep Health ; 5(2): 166-174, 2019 04.
Article in English | MEDLINE | ID: mdl-30928117

ABSTRACT

BACKGROUND: Sleep health can be characterized using multiple dimensions, including regularity, satisfaction, alertness, timing, efficiency, and duration. This study provides a preliminary derivation of a Sleep Health Composite score in adolescents with eveningness chronotype and examined its associations with mental and physical health outcomes. METHODS: Participants were 176 adolescents (mean age 14.77 years, 58% female) who participated in a randomized controlled trial examining the Transdiagnostic Sleep and Circadian intervention. At study entry, the sample was characterized by evening circadian preference, later bedtime, and increased risk in 1 of 5 health domains (emotional, cognitive, behavioral, social, and physical). The Sleep Health Composite was derived using 7-day sleep diary and self-report rating scales. Each dimension was categorized as "good" or "poor" using cut-offs informed by prior studies and expert consensus. Mental and physical health outcomes were assessed using self-report rating scales, semistructured clinical interviews, parent report, or biometric measurement. RESULTS: Sleep duration and satisfaction dimensions were most commonly rated as poor. Greater sleep health, as indexed by greater Sleep Health Composite score, was concurrently associated with lower risk in emotional, cognitive, and social domains, as well as fewer physical symptoms and reduced odds for obesity and current mood or anxiety disorders. CONCLUSIONS: Sleep health is an important correlate of mental and physical health outcomes in adolescents. The Sleep Health Composite has potential application as an outcome measure in treatment studies of sleep and circadian problems.


Subject(s)
Anxiety Disorders/epidemiology , Circadian Rhythm , Mood Disorders/epidemiology , Pediatric Obesity/epidemiology , Sleep , Adolescent , Female , Humans , Male , Risk Factors , Self Report , Time Factors
8.
J Med Food ; 20(11): 1133-1139, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28777691

ABSTRACT

Sterculia apetala (order: Malvales, family: Sterculiaceae) seed oil contains two cyclopropene fatty acids: sterculic and malvalic acid. Both positive and negative effects have been associated with the consumption of sterculic oil. In Mexico, S. apetala seeds are consumed after being boiled or roasted, used as chocolate flavoring, and utilized as animal fodder. Therefore, it is important to evaluate whether the consumption of this seed has a negative impact on the organism. The aim of this study was to evaluate the effect of administration of sterculic oil, during an 8-week period, on anxiety-like behavior and spontaneous locomotor activity in Zucker rats, analyzed through light/dark and open-field tests. The results showed that the consumption of sterculic oil decreased exploration latency in light/dark tests, which suggests an anxiolytic-like effect. Alterations in time spent on rearing and grooming were present in open-field tests, but this was not statistically significant, discarding nonspecific motor alterations. The alterations found in this study are possibly related to intrinsic obesity and metabolic complications present in the Zucker rat model, where leptin plays an important role in animal mood, more so than sterculic oil consumption.


Subject(s)
Anti-Anxiety Agents/administration & dosage , Anxiety/drug therapy , Anxiety/psychology , Plant Oils/administration & dosage , Sterculia/chemistry , Animals , Anti-Anxiety Agents/chemistry , Anxiety/etiology , Behavior, Animal/drug effects , Humans , Male , Obesity/complications , Obesity/drug therapy , Obesity/psychology , Plant Oils/chemistry , Rats , Rats, Zucker , Seeds/chemistry
9.
Gac. sanit. (Barc., Ed. impr.) ; 31(4): 286-291, jul.-ago. 2017. graf, tab
Article in Spanish | IBECS | ID: ibc-164369

ABSTRACT

Objetivo: Identificar la asociación de distintas variables sociodemográficas con el gasto de bolsillo en servicios de salud en adultos de 60 años y más afiliados al Seguro Popular (SP). Método: Estudio transversal analítico. Se realizó una encuesta a través de una entrevista cara a cara a usuarios de la consulta externa de tres unidades médicas del estado de Veracruz: centro de salud (primer nivel), hospital regional (segundo nivel) y hospital de alta especialidad. El gasto de bolsillo en salud en el último año se analizó con el modelo lineal generalizado. Resultados La muestra fue de 1049 adultos de 60 años y más beneficiarios del SP y la tasa de respuesta fue del 97,7%. El gasto de bolsillo en salud mensual fue US$ 64,8 (intervalo de confianza del 95% [IC95%]: 59,9-69,8). El rubro con mayor gasto fueron los medicamentos incluidos en el SP (US$ 28,8; IC95%: 25,8-31,7) y los medicamentos que no cubre el SP (US$ 8; IC95%: 6,7-9,2). Conclusiones Los adultos de 60 años y más afiliados al SP pagan de su bolsillo para atender su salud, a pesar de contar con un seguro público de salud, lo que representa una inequidad en el acceso, principalmente para los más vulnerables, como son la población rural (AU)


Objective: To identify the association between various sociodemographic variables and out-of-pocket expenditure on health by elderly people enrolled in Seguro Popular (SP). Method: Analytical cross-sectional study. An in-person survey was administered to users of three outpatient clinics in the state of Veracruz: a health centre (first level), regional hospital (second level) and highly specialised hospital. The out-of-pocket expenditure on health was analysed using a generalised linear model. Results: The sample consisted of 1,049 beneficiaries of SP over age 60 with a response rate of 97.7%. The monthly out-of-pocket expenditure on health was $64.80 (95% confidence interval [95% CI]: 59.90–69.80). The highest expense category was drugs that are included in the SP ($28.80; 95% CI: 25.80–31.70) and drugs that are not covered by the SP ($8.00; 95% CI: 6.70–9.20). Conclusions: People over age 60 enrolled in SP pay out of their pocket to meet their health needs, despite having public health insurance. This represents an inequity in access, especially for the most vulnerable such as the rural population (AU)


Subject(s)
Humans , Aged , Cost of Illness , Health Services for the Aged/statistics & numerical data , Health Expenditures/statistics & numerical data , Cost Sharing/statistics & numerical data , Mexico , Insurance, Health/statistics & numerical data , Cross-Sectional Studies , Health Care Surveys/statistics & numerical data
10.
Gac Sanit ; 31(4): 286-291, 2017.
Article in Spanish | MEDLINE | ID: mdl-28249704

ABSTRACT

OBJECTIVE: To identify the association between various sociodemographic variables and out-of-pocket expenditure on health by elderly people enrolled in Seguro Popular (SP). METHOD: Analytical cross-sectional study. An in-person survey was administered to users of three outpatient clinics in the state of Veracruz: a health centre (first level), regional hospital (second level) and highly specialised hospital. The out-of-pocket expenditure on health was analysed using a generalised linear model. RESULTS: The sample consisted of 1,049 beneficiaries of SP over age 60 with a response rate of 97.7%. The monthly out-of-pocket expenditure on health was $64.80 (95% confidence interval [95% CI]: 59.90-69.80). The highest expense category was drugs that are included in the SP ($28.80; 95% CI: 25.80-31.70) and drugs that are not covered by the SP ($8.00; 95% CI: 6.70-9.20). CONCLUSIONS: People over age 60 enrolled in SP pay out of their pocket to meet their health needs, despite having public health insurance. This represents an inequity in access, especially for the most vulnerable such as the rural population.


Subject(s)
Health Expenditures , Insurance, Health/economics , Aged , Cross-Sectional Studies , Female , Humans , Male , Mexico , Middle Aged , Public Health , Socioeconomic Factors
11.
Ann Bot ; 115(5): 833-40, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25681823

ABSTRACT

BACKGROUND AND AIMS: Rhizophora species of mangroves have a conspicuous system of stilt-like roots (rhizophores) that grow from the main stem and resemble flying buttresses. As such, the development of rhizophores can be predicted to be important for the effective transmission of dynamic loads from the top of the tree to the ground, especially where the substrate is unstable, as is often the case in the habitats where Rhizophora species typically grow. This study tests the hypothesis that rhizophore architecture in R. mangle co-varies with their proximity to the main stem, and with stem size and crown position. METHODS: The allometry and wood mechanical properties of R. mangle (red mangrove) trees growing in a mangrove basin forest within a coastal lagoon in Mexico were compared with those of coexisting, non-buttressed mangrove trees of Avicennia germinans. The anatomy of rhizophores was related to mechanical stress due to crown orientation (static load) and to prevailing winds (dynamic load) at the study site. KEY RESULTS: Rhizophores buttressed between 10 and 33 % of tree height. There were significant and direct scaling relationships between the number, height and length of rhizophores vs. basal area, tree height and crown area. Wood mechanical resistance was significantly higher in the buttressed R. mangle (modulus of elasticity, MOE = 18·1 ± 2 GPa) than in A. germinans (MOE = 12·1 ± 0·5 GPa). Slenderness ratios (total height/stem diameter) were higher in R. mangle, but there were no interspecies differences in critical buckling height. When in proximity to the main stem, rhizophores had a lower length/height ratio, higher eccentricity and higher xylem/bark and pith proportions. However, there were no directional trends with regard to prevailing winds or tree leaning. CONCLUSIONS: In comparison with A. germinans, a tree species with wide girth and flare at the base, R. mangle supports a thinner stem of higher mechanical resistance that is stabilized by rhizophores resembling flying buttresses. This provides a unique strategy to increase tree slenderness and height in the typically unstable substrate on which the trees grow, at a site that is subject to frequent storms.


Subject(s)
Avicennia/physiology , Plant Roots/physiology , Rhizophoraceae/physiology , Animals , Avicennia/anatomy & histology , Biomechanical Phenomena , Ecology , Ecosystem , Mexico , Plant Roots/anatomy & histology , Plant Stems/anatomy & histology , Plant Stems/physiology , Rhizophoraceae/anatomy & histology , Trees , Wetlands , Wind , Wood/anatomy & histology , Wood/physiology , Xylem/anatomy & histology , Xylem/physiology
12.
Int J Dev Neurosci ; 41: 68-73, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25578294

ABSTRACT

The effects of stimulating environments on the neural plasticity of the adult brain have been well explored; however, how an enriched environment (EE) affects the mother-fetus interaction is poorly understood. We hypothesized that an enriched environment restricted to pregnancy will succeed in accelerating the development of sensory and motor circuits in the offspring. Pregnant Wistar rats were maintained either under a standard condition - two animals per standard cage- or an enriched environment - eight subjects in larger cages with different physical configurations-. After birth, litters from both groups (n=16 per group) were cross-fostered with mothers that were simultaneously maintained under standard environment during pregnancy. Sensory and motor development were studied in the pups of both groups with a battery of reflex and physical tests. Auditory and gait reflexes appeared two days earlier in the offspring of EE rats as compared to control subjects (p<0.05). In addition, EE pups displayed a better performance in righting reflex, inclined board and geotaxis tests (p<0.05). Differences were found even three weeks after birth. We conclude that EE limited to the phase of pregnancy stimulates the development of pups inutero so that they are born with a higher grade of development.


Subject(s)
Environment , Muscle Strength/physiology , Prenatal Exposure Delayed Effects , Reflex, Startle/physiology , Sensory Gating/physiology , Acoustic Stimulation , Age Factors , Animals , Animals, Newborn , Body Weight , Female , Litter Size , Male , Pregnancy , Psychomotor Performance/physiology , Rats , Rats, Wistar
13.
Ter. psicol ; 32(3): 235-242, Dec. 2014. tab
Article in Spanish | LILACS | ID: lil-734894

ABSTRACT

El objetivo de esta investigación fue analizar la asociación entre autoeficacia percibida, personalidad resistente, locus de control, percepción de estrés y síndrome de Burnout en 40 estudiantes de medicina de pregrado. El análisis de los datos se efectuó considerando estadística descriptiva y técnicas exploratorias multivariadas. Los resultados muestran la pertinencia que puede tener la personalidad resistente en la atenuación del estrés crónico al asociarse negativamente con el síndrome de Burnout y agruparse dentro de los componentes que explicaban mayor variación en la combinación lineal de variables en comparación con la autoeficacia y el locus de control. Se confirma la necesidad de reforzar la formación de los estudiantes de medicina a través del establecimiento de recursos de afrontamiento ante el estrés y formación de una personalidad resistente, ya que los datos muestran niveles altos en percepción de estrés y síndrome de Burnout a seis meses de estar realizando el internado.


The objective of this research was to analyze the association between perceived self-efficacy, hardiness, locus of control, perceived stress and Burnout syndrome in 40 undergraduate medical students. The data analysis was performed considering descriptive statistics and multivariate exploratory techniques. The results show the relevance that may have the hardiness in the attenuation of chronic stress negatively associated with Burnout and grouped within components that explained more variation in the linear combination of variables compared to self-efficacy and locus of control. The need to strengthen the training of medical students through the establishment of resources Coping Stress and formation of a strong personality is confirmed as the data show high levels of perceived stress and Burnout six months of doing the internship.


Subject(s)
Humans , Male , Female , Burnout, Professional/psychology , Students, Medical/psychology , Personality , Principal Component Analysis , Self Efficacy , Education, Medical, Undergraduate , Epidemiology, Descriptive , Surveys and Questionnaires
14.
Eur J Neurosci ; 35(9): 1458-65, 2012 May.
Article in English | MEDLINE | ID: mdl-22471601

ABSTRACT

Rabbit pups represent a natural model of food anticipatory activity (FAA). FAA is the behavioral output of a putative food entrainable oscillator (FEO). It had been suggested that the FEO is comprised of a distributed system of clocks that work in concert in response to gastrointestinal input by food. Scheduled food intake synchronizes several nuclei in the brain, and the hypothalamus has received particular attention. On the contrary, brainstem nuclei, despite being among the brain structures to first receive food cues, have been scarcely studied. Here we analysed by immunohistochemistry possible oscillation of FOS and PER1 proteins through a complete 24-h cycle in the dorsal vagal complex (DVC) and parabrachial nucleus (PBN) of 7-8-day-old rabbit pups scheduled to nurse during the night (02:00 h) or day (10:00 h), and also in fasted subjects to explore the possible persistence of oscillations. We found a clear induction of FOS that peaks 1.5 h after nursing in all nuclei studied. PER1 was only synchronized in the PBN, reaching highest values 12 h after nursing. Only PER1 oscillations persisted, with a shift, in fasted subjects. We conclude that the DVC nuclei are probably more related to the transmission of food cues to other brain regions, but that the PBN participates in the integration of information essential for FAA. Our results support previous findings suggesting that the DVC nuclei, but not PBN, are not essential for FAA. We suggest that PBN is a key component of the proposed distributed system of clocks involved in FAA.


Subject(s)
Circadian Rhythm/physiology , Feeding Behavior/physiology , Period Circadian Proteins/metabolism , Pons/metabolism , Age Factors , Analysis of Variance , Animals , Animals, Newborn , Eating/physiology , Female , Gene Expression Regulation, Developmental , Medulla Oblongata/anatomy & histology , Medulla Oblongata/metabolism , Motor Activity , Oncogene Proteins v-fos/metabolism , Rabbits
15.
Am J Bot ; 91(7): 1061-9, 2004 Jul.
Article in English | MEDLINE | ID: mdl-21653462

ABSTRACT

By definition, the floral morphs of distylous plants differ in floral architecture. Yet, because cross-pollination is necessary for reproductive success in both morphs, they should not differ in attributes that contribute to attracting and rewarding floral visitors. Floral and vegetative attributes that function in distylous polymorphism in hummingbird-pollinated Palicourea padifolia (Rubiaceae) and the responses of pollinators and insect herbivores to the resources offered by both morphs were investigated. The performance of each morph along multiple stages of the reproductive cycle, from inflorescence and nectar production to fruit production, was surveyed, and pollinator behavior and nectar standing crops were then observed. Costs associated with such attractiveness were also evaluated in terms of herbivore attack and of plant reproductive fitness (female function) as a function of leaf herbivory. The number of inflorescences, floral buds, open flowers, and ripe fruits offered by either floral morph were similar, but short-styled plants almost doubled the number of developing fruits of long-styled plants. Long-styled flowers produced higher nectar volumes and accumulated more nectar over time than short-styled flowers. Measures of nectar standing crop and data on pollinator behavior suggest that hummingbirds respond to this morph-specific scheduling of nectar production. Lastly, long-styled plants suffered a higher herbivore attack and lost more leaf area over time than those with short-styled flowers. Herbivory was negatively correlated with fruit number and fruit mass, and long-styled plants set significantly less fruit mass than short-styled plants. The results suggest that pollinators and herbivores may exert selective pressures on floral and vegetative traits that could also influence gender function.

16.
Ann Bot ; 92(3): 365-75, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12871845

ABSTRACT

Browsing is an important mortality factor in seedlings and small plants. However, the induced changes in the architecture of plant survivors may influence subsequent browsing, opening the possibility of compensating for the damage done. How jackrabbit (Lepus californicus) browsing affects the growth and architecture of small individuals of honey mesquite, Prosopis glandulosa var. torreyana, a tree/shrub that produces spines at every node, was explored. Naturally established mesquites of unknown age were selected in one site, and 2-year-old mesquites were transplanted in another site. In both cases, half of them were exposed to jackrabbits and the other half were excluded as controls. After 4 years, shoot production (height, length and number of derived shoots) and plant growth (height and cover) increased 1.4-2.5-fold in naturally established controls relative to exposed plants, depending on the measured variable. In the transplant experiment, the increases were 2.8-7.1-fold in controls relative to exposed plants 2 years after initiation of the experiment. The net loss of biomass in treatment vs. control plants in these experiments suggests a negative response to browsing which has been defined as under-compensation. Alternative architectures in honey mesquites were evident at the end of the exclusion experiments: controls had long branches and an extended crown cover, while exposed plants had short branches and a compact crown cover. Results indicated that mesquites were able to grow under browser pressure by packing many stems in a compact matrix armed with spines and producing one or more shoots tall and wide enough to escape from jackrabbits.


Subject(s)
Prosopis/growth & development , Animals , Feeding Behavior , Flowers/growth & development , Hares , Meristem/growth & development , Plant Shoots/growth & development , Plant Stems/growth & development
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