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1.
Glob Chang Biol ; 30(1): e17106, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38273553

ABSTRACT

Global surface temperatures are projected to increase in the future; this will modify regional precipitation regimes and increase global atmospheric drying. Despite many drought studies examining the consequences of reduced precipitation, there are few experimental studies exploring plant responses to atmospheric drying via relative humidity and vapor pressure deficit (VPD). We examined eight native California perennial grass species grown in pots in a greenhouse in Los Angeles, California for 34 weeks. All pots were well-watered for 21 weeks, at which point we reduced watering to zero and recorded daily growth and dormancy for 3 weeks. We used this information to better understand the drought tolerance of our species in a larger soil drying × atmospheric drying experiment. In this larger experiment, we grew all eight species together in outdoor mesocosms and measured changes in community composition after 4 years of growth. Soil drying in our small pot experiment mirrored compositional shifts in the larger experiment. Namely, our most drought-tolerant species in our pot experiment was Poa secunda, due to a summer dormancy strategy. Similarly, the grass community shifted toward P. secunda in the driest soils as P. secunda was mostly unaffected by either soil drying or atmospheric drying. We found that some species responded strongly to soil drying (Elymus glaucus, Festuca idahoensis, and Hordeum b. californicum), while others responded strongly to atmospheric drying (Bromus carinatus and Stipa cernua). As result, community composition shifted in different and interacting ways in response to soil drying, atmospheric drying, and their combination. Further study of community responses to increasing atmospheric aridity is an essential next step to predicting the future consequences of climate change.


Subject(s)
Poaceae , Soil , Droughts , Plants , Seasons
2.
Phys Rev Lett ; 131(10): 105101, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37739360

ABSTRACT

In direct-drive inertial confinement fusion, the laser bandwidth reduces the laser imprinting seed of hydrodynamic instabilities. The impact of varying bandwidth on the performance of direct-drive DT-layered implosions was studied in targets with different hydrodynamic stability properties. The stability was controlled by changing the shell adiabat from (α_{F}≃5) (more stable) to (α_{F}≃3.5) (less stable). These experiments show that the performance of lower adiabat implosions improves considerably as the bandwidth is raised indicating that further bandwidth increases, beyond the current capabilities of OMEGA, would be greatly beneficial. These results suggest that the future generation of ultra-broadband lasers could enable achieving high convergence and possibly high gains in direct drive ICF.

3.
Sci Rep ; 13(1): 9244, 2023 06 07.
Article in English | MEDLINE | ID: mdl-37286701

ABSTRACT

Chronic endemic regional hydroarsenicism (CERHA) is a global issue that affects over 200 million people exposed to arsenic (As) in drinking water. This includes 1.75 million individuals residing in La Comarca Lagunera, a region in north-central Mexico. Arsenic levels in this region typically exceeds the WHO guideline of 10 µg L-1. Biochemical alterations related to the human As metabolism may increase the risk of overweight and obesity (O&O), type 2 diabetes (T2D), and hypertension (AHT). In our study, we investigated the role of As in drinking water as a risk factor for these metabolic diseases. We focused on populations with historically moderate (San Pedro) and low (Lerdo) drinking water As levels and people with no historical evidence of As water contamination. The exposure assessment to As was based on measurements of the drinking water (medians 67.2, 21.0, 4.3 µg L-1) and urinary As concentrations in women (9.4, 5.3, 0.8 µg L-1) and men (18.1, 4.8, 1.0 µg L-1). A significant correlation between As in drinking water and urine evidenced the As exposure in the population (R2 = 0.72). Adjusted odds ratios with 95% confidence intervals evidenced higher chances of being diagnosed with T2D (1.7, 1.2-2.0) and AHT (1.8, 1.7-1.9) in individuals living in San Pedro than those in Lerdo. Still, there was no significant association with obesity. Individuals living in CERHA towns were found to have a higher risk of obesity (1.3-1.9), T2D (1.5 to 3.3), and AHT (1.4 to 2.4) compared to those residing in non-CERHA towns. Finally, obesity is more probable in women [inverse of OR and 95%CI 0.4 (0.2-0.7)] compared to men, while men is more likely to be diagnosed with T2D [OR = 2.0 (1.4-2.3)] and AHT [OR = 2.0 (1.5-2.3)] than women, independently of the municipality.


Subject(s)
Arsenic , Diabetes Mellitus, Type 2 , Drinking Water , Hypertension , Water Pollutants, Chemical , Male , Humans , Female , Arsenic/toxicity , Arsenic/analysis , Drinking Water/adverse effects , Drinking Water/analysis , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/etiology , Mexico/epidemiology , Water Pollutants, Chemical/toxicity , Hypertension/epidemiology , Hypertension/etiology , Obesity/epidemiology , Environmental Exposure/adverse effects
4.
Poult Sci ; 102(2): 102328, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36476681

ABSTRACT

Japanese quails in wild life live in small groups with females being even solitary during the laying period. Although it is a poultry species widely used for egg production, information regarding laying behavior motivations or influencing variables is scarce. Our study focuses on evaluating along 7 d the quail laying behavior in a novel environmental set up. This set up allows the female to choose between remaining separated from a conspecific in one side of the apparatus or to voluntarily enter their space (box-mate side) and interact with it. We evaluated whether the female insemination status prior to enter the environmental set up, and the presence of a female or a male partner in the box-mate side can influence their laying and social behavior. Thus, 4 experimental groups were established. Females spent a higher (P < 0.05) percentage of time in the box-mate side than in their separated sector in all groups. In 3 of the 4 experimental groups (non-inseminated females interacting with a female or a male box-mate, and inseminated females interacting with a male box-mate) females also laid a greater percentage (≥65%, P < 0.05, in all cases) of eggs in the box-mate sector than in their separated sector. However, the group of inseminated females that interacted with a female box-mate shifted their egg distribution and laid equally between both sides of the apparatus. Aggressive social interactions were reduced (P < 0.05) throughout the testing days but this was depending upon the female insemination status and the sex of their box-mate. Findings suggest that females can change their laying side choice when they are inseminated but depending on the sex identity of their box-mate partners. Thus, providing quail female breeders with the option of laying their eggs in separated enclosures from conspecifics could be key to favor their well-being.


Subject(s)
Oviposition , Quail , Female , Male , Animals , Chickens , Ovum , Coturnix , Social Behavior , Insemination , Social Environment
5.
Psychoneuroendocrinology ; 146: 105947, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36242820

ABSTRACT

Early life adversity/stress (ELA/ELS), particularly adverse caregiving experiences such as child maltreatment (MALT), is a main risk factor for psychopathology, including psychiatric disorders such as anxiety, depression, ADHD, and substance abuse. Yet how these alterations unfold during development and the underlying mechanisms remain poorly understood, as it is difficult to prospectively and longitudinally study early developmental phases in humans, and nearly impossible to disentangle postnatal caregiving effects from heritable traits. This study examined the specific effects of "nurture" (maternal care) versus "nature" (heritable, biological maternal factors) on nonhuman primate infant socioemotional, stress neuroendocrine, and physical development. For this we used a translational and naturalistic macaque model of infant maltreatment by the mother with randomized assignment at birth to either mothers with a history of maltreating their infants (MALT group, n = 22) or to competent mothers (Control group, n = 20). Over the first 6 months of life (roughly equivalent to 2 years in humans), we examined the development of the mother-infant relationship, as well as infants' social behavior and emotional reactivity. In parallel, we assessed hypothalamic-pituitary-adrenal (HPA) axis function longitudinally, using measures of hair cortisol accumulation, and basal morning plasma cortisol. We identified broad impairments in maternal care exhibited by MALT foster mothers, beyond maltreatment (physical abuse, rejection) events, suggesting that MALT foster mothers provide an overall lower quality of care to their infants compared to Controls. MALT infants exhibited alterations in their initiations and breaks of proximity towards their mothers, as well as heightened emotional reactivity in comparison to Controls. Most striking are the HPA axis findings, with MALT infants showing higher levels of plasma cortisol across the first 6 postnatal months as well as higher hair cortisol accumulation from birth through month 6 (a signature of chronic stress) than Controls. No caregiving effects were detected on physical growth, which ruled out confounding effects of maternal nutrition, metabolism, etc. Taken together, these results suggest that the developmental trajectory of MALT and Control infants is different, marked by heightened levels of emotional reactivity, increased HPA activity and alterations in mother-infant interactions in MALT animals. These findings appear to be due to specific effects of postnatal maternal care, and not to biological/ behavioral traits inherited from the mother, or due to prenatal programming caused by prenatal stress, as the cross-fostering design controlled for these potential factors. However, we also detected a couple of interesting biological effects suggesting heritable transmission of some phenotypes. The prolonged HPA axis activation during the first 6 postnatal months of life is expected to have long-term consequences for brain, physiological, and behavioral development in MALT offspring.

7.
Poult Sci ; 100(3): 100950, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33518317

ABSTRACT

Test of sociality in poultry is mainly based on the bird's individual ability to make quick social discriminations. In recent years, a density-related permanence (DRP) test has been developed that enables us to classify young birds (while in groups) according to their individual permanence in proximity to either a high or low density of conspecifics (HD or LD, respectively). Thus, the result of the classification depends not only on the bird's individual response but also on the outcome of the social interactions within the whole group. The birds' performance in DRP was associated with underlying differences in social responses of their individuals. Quails in homogeneous groups of LD residents responded with less compact groups and higher levels of agonistic interactions to the presence of an intruder and showed higher levels of agonistic interactions among cage-mates than the homogeneous groups of HD birds. An acute stressor also induced a higher corticosterone response in the LD birds than in their HD counterparts. The present study addressed the question of whether contrasting DRP performance by Japanese quail can also reflect underlying differences in fearfulness and social reinstatement responses. Thus, LD and HD categorized juvenile birds underwent one of the following tests: tonic immobility (TI), open-field (OF), or a one-way runway. Results showed that HD birds required more inductions and developed shorter responses (P ≤ 0.05) in the TI test and walked more, faster, and greater distances in the OF (P ≤ 0.05) than their LD counterparts. No differences between groups were found in short social reinstatement responses. The present findings suggest that underlying fearfulness is lower in the HD than in the LD birds. A reduced fearfulness could be regarded as an additional favorable trait of the HD-classified quail to cope with environmental challenging situations.


Subject(s)
Coturnix , Social Behavior , Animals , Corticosterone/blood , Coturnix/blood , Coturnix/physiology , Fear , Population Density , Stress, Psychological/blood
8.
Microb Genom ; 6(5)2020 05.
Article in English | MEDLINE | ID: mdl-32176604

ABSTRACT

Clostridium difficile B1/NAP1/RT027/ST01 has been responsible for outbreaks of antibiotic-associated diarrhoea in clinical settings worldwide and is associated with severe disease presentations and increased mortality rates. Two fluoroquinolone-resistant (FQR) lineages of the epidemic B1/NAP1/RT027/ST01 strain emerged in the USA in the early 1990s and disseminated trans continentally (FQR1 and FQR2). However, it is unclear when and from where they entered Latin America (LA) and whether isolates from LA exhibit unique genomic features when compared to B1/NAP1/RT027/ST01 isolates from other regions of the world. To answer the first issue we compared whole-genome sequences (WGS) of 25 clinical isolates typed as NAP1, RT027 or ST01 in Costa Rica (n=16), Chile (n=5), Honduras (n=3) and Mexico (n=1) to WGS of 129 global isolates from the same genotype using Bayesian phylogenomics. The second question was addressed through a detailed analysis of the number and type of mutations of the LA isolates and their mobile resistome. All but two B1/NAP1/RT027/ST01 isolates from LA belong to the FQR2 lineage (n=23, 92 %), confirming its widespread distribution. As indicated by analysis of a dataset composed of 154 WGS, the B1/NAP1/RT027/ST01 strain was introduced into the four LA countries analysed between 1998 and 2005 from North America (twice) and Europe (at least four times). These events occurred soon after the emergence of the FQR lineages and more than one decade before the first report of the detection of the B1/NAP1/RT027/ST01 in LA. A total of 552 SNPs were identified across all genomes examined (3.8-4.3 Mb) in pairwise comparisons to the R20291 reference genome. Moreover, pairwise SNP distances were among the smallest distances determined in this species so far (0 to 55). Despite this high level of genomic conservation, 39 unique SNPs (7 %) in genes that play roles in the infection process (i.e. slpA) or antibiotic resistance (i.e. rpoB, fusA) distinguished the LA isolates. In addition, isolates from Chile, Honduras and Mexico had twice as many antibiotic resistance genes (ARGs, n=4) than related isolates from other regions. Their unique set of ARGs includes a cfr-like gene and tetM, which were found as part of putative mobile genetic elements whose sequences resemble undescribed integrative and conjugative elements. These results show multiple, independent introductions of B1/NAP1/RT027/ST01 isolates from the FQR1 and FQR2 lineages from different geographical sources into LA and a rather rapid accumulation of distinct mutations and acquired ARG by the LA isolates.


Subject(s)
Clostridioides difficile/classification , Drug Resistance, Multiple, Bacterial , Fluoroquinolones/pharmacology , Polymorphism, Single Nucleotide , Whole Genome Sequencing/methods , Bayes Theorem , Chile , Clostridioides difficile/drug effects , Clostridioides difficile/genetics , Clostridioides difficile/isolation & purification , Costa Rica , Europe , Evolution, Molecular , Feces/microbiology , Genome, Bacterial , High-Throughput Nucleotide Sequencing , Honduras , Humans , Mexico , Phylogeny , Phylogeography , United States
9.
Article in English, Spanish | MEDLINE | ID: mdl-31519537

ABSTRACT

INTRODUCTION: The management of postoperative pain in joint replacement surgery represents a challenge. Therefore, the advent of new strategies in the management of pain such as local infiltration analgesia (LIA) and the adductor canal block, allowed an adequate postoperative pain control and early rehabilitation of the patient in total knee arthroplasty. MATERIALS AND METHODS: A descriptive, observational and longitudinal study of a prospective cohort of patients operated by the group of joint replacements between September 29, 2017 and November 30, 2017 was conducted. They were evaluated with the analog pain scale for postoperative pain at 5 different times (1:Upon leaving recovery; 2:On the first postoperative day; 3:Before initiating in-hospital physical therapy; 4:At the end of physical therapy, and 5:Upon departure from the clinic). RESULTS: Of the 141 patients operated on, 70.9% of the patients were managed with LIA and 29.1% with adductor canal block. There were no differences between groups in postoperative pain assessment during the 5 different times (P≥.45). DISCUSSION: Our results indicate that LIA and the adductor canal blockade demonstrated the same efficacy for the control of postoperative pain and rehabilitation.


Subject(s)
Anesthesia, Local , Arthroplasty, Replacement, Knee , Nerve Block , Pain Management/methods , Pain, Postoperative/therapy , Recovery of Function , Humans , Longitudinal Studies , Middle Aged , Prospective Studies , Time Factors
10.
J Public Health (Oxf) ; 41(2): 240-249, 2019 06 01.
Article in English | MEDLINE | ID: mdl-29617886

ABSTRACT

BACKGROUND: The US homeless population is aging. Older adults and those living in poverty are at a high risk of food insecurity. METHODS: We conducted a cross-sectional analysis of baseline data from a population-based study of 350 homeless adults aged ≥50. We assessed food security and receipt of food assistance. We used multivariable logistic regression to examine factors associated with very low food security. RESULTS: The majority of the cohort was male and African American. Over half (55.4%) met criteria for food insecurity, 24.3% reported very low food security. Half (51.7%) reported receiving monetary food assistance. In the multivariable model, those who were primarily sheltered in the prior 6 months, (multi-institution users [AOR = 0.44, 95% CI: 0.22-0.86]) had less than half the odds of very low food security compared with those who were unsheltered. Depressive symptoms (AOR = 3.01, 1.69-5.38), oral pain (AOR = 2.15, 1.24-3.74) and cognitive impairment (AOR = 2.21, 1.12-4.35) were associated with increased odds of very low food security. CONCLUSIONS: Older homeless adults experience a high prevalence of food insecurity. To alleviate food insecurity in this population, targeted interventions must address specific risk groups.


Subject(s)
Food Supply/statistics & numerical data , Ill-Housed Persons/statistics & numerical data , Cognitive Dysfunction/epidemiology , Cross-Sectional Studies , Depression/epidemiology , Depression/etiology , Female , Food Assistance/statistics & numerical data , Ill-Housed Persons/psychology , Humans , Male , Middle Aged , Risk Factors , United States
11.
Poult Sci ; 97(11): 4107-4112, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-29924361

ABSTRACT

The density-related permanence test (DRP) is used to classify young birds (while in groups) according to their individual permanence in proximity to either a high or low density of conspecifics (HD or LD, respectively). The birds' performance in DRP was associated with underlying differences in the social responses of their individuals. Quails in homogeneous groups of LD residents responded with less compact groups and higher levels of agonistic interactions to the presence of an intruder, and showed higher levels of agonistic interactions among cagemates than the homogeneous groups of HD birds. This study deepen the characterization of DRP evaluating whether contrasting behavior during test is associated with birds' stress responses to challenging situations during rearing. Plasma corticosterone responses were individually assessed after submitting DRP categorized birds to a brief (10 min) partial restraint (mechanical stressor; experiment 1), or after introducing them during 5 min as intruders in homogeneous groups of 6 unknown same category (HD or LD) conspecifics (social stressor; experiment 2). Experiment 1 showed that basal corticosterone levels were similar in all groups and the partial mechanical restraint induced an increase in plasma corticosterone concentration also in all groups. However, the increase induced by the stressor was higher in the LD birds than in their HD counterparts. In experiment 2, compared to controls, social stressor showed no plasma corticosterone changes in the intruders that were introduced in an unfamiliar group of HD conspecifics. However, intruders (both HD and LD) that were visiting the LD residents showed an increased corticosterone response compared to their control counterparts. Results suggest that categorization of birds in the DRP test could have relevance for selection programs oriented to obtain birds better suited to intensive rearing conditions that includes high density of animals and exposure to unavoidable stressors.


Subject(s)
Adrenal Cortex/physiology , Corticosterone/blood , Coturnix/physiology , Stress, Physiological , Animal Welfare , Animals , Female , Male , Population Density , Restraint, Physical/veterinary , Stress, Psychological
12.
Clin Exp Immunol ; 192(3): 284-291, 2018 06.
Article in English | MEDLINE | ID: mdl-29878323

ABSTRACT

This is the second report of the United Kingdom Primary Immunodeficiency (UKPID) registry. The registry will be a decade old in 2018 and, as of August 2017, had recruited 4758 patients encompassing 97% of immunology centres within the United Kingdom. This represents a doubling of recruitment into the registry since we reported on 2229 patients included in our first report of 2013. Minimum PID prevalence in the United Kingdom is currently 5·90/100 000 and an average incidence of PID between 1980 and 2000 of 7·6 cases per 100 000 UK live births. Data are presented on the frequency of diseases recorded, disease prevalence, diagnostic delay and treatment modality, including haematopoietic stem cell transplantation (HSCT) and gene therapy. The registry provides valuable information to clinicians, researchers, service commissioners and industry alike on PID within the United Kingdom, which may not otherwise be available without the existence of a well-established registry.


Subject(s)
Epidemiological Monitoring , Immunologic Deficiency Syndromes/epidemiology , Registries/statistics & numerical data , Female , Humans , Immunologic Deficiency Syndromes/immunology , Immunologic Deficiency Syndromes/therapy , Male , United Kingdom/epidemiology
13.
J Gen Intern Med ; 33(5): 635-643, 2018 05.
Article in English | MEDLINE | ID: mdl-29185174

ABSTRACT

BACKGROUND: The homeless population in the United States is aging. Aging-associated comorbidities are associated with increased symptoms. OBJECTIVE: To describe the prevalence of symptoms among older homeless-experienced adults, analyze factors associated with moderate-high physical symptom burden, and identify symptom clusters. DESIGN: Cross-sectional analysis within longitudinal cohort study. PARTICIPANTS: Using population-based sampling from shelters, meal programs, encampments, and a recycling center in Oakland, CA, we recruited homeless adults aged ≥ 50 for a longitudinal cohort. This study includes participants who participated in the 18-month follow-up visit. MAIN MEASURES: We assessed physical symptoms using the Patient Health Questionnaire-15 (PHQ-15); psychological symptoms using the Center for Epidemiologic Studies Depression Scale (CES-D), Primary Care PTSD Screen (PC-PTSD), and psychiatric section of the Addiction Severity Index (ASI); loneliness using the Three-Item Loneliness Scale; and regret using a six-item regret scale. KEY RESULTS: Two hundred eighty-three participants (75.6% men and 82.3% African-Americans) completed symptoms interviews. Over a third (34.0%) had moderate-high physical symptom burden. The most prevalent physical symptoms were joint pain, fatigue, back pain, and sleep trouble. Over half (57.6%) had psychological symptoms; 39.6% exhibited loneliness and 26.5% had high regret. In a multivariate model, being a woman (AOR 2.54, 95% CI 1.28-5.03), childhood abuse (AOR 1.88, 95% CI 1.00-3.50), cannabis use (AOR 2.59, 95% CI 1.38-4.89), multimorbidity (AOR 2.50, 95% CI 1.36-4.58), anxiety (AOR 4.30, 95% CI 2.24-8.26), hallucinations (AOR 3.77, 95% CI 1.36-10.43), and loneliness (AOR 2.32, 95% CI 1.26-4.28) were associated with moderate-high physical symptom burden. We identified four symptom clusters: minimal overall (n = 129), moderate overall (n = 68), high physical and high psychological (n = 67), and high physical and low psychological (n = 17). CONCLUSIONS: Older homeless-experienced adults exhibit a high prevalence of symptoms across multiple dimensions. To reduce suffering, clinicians should recognize the interaction between symptoms and address multiple symptom dimensions.


Subject(s)
Health Status , Ill-Housed Persons/psychology , Aged , Aging/physiology , California , Cluster Analysis , Cross-Sectional Studies , Female , Humans , Longitudinal Studies , Male , Middle Aged , Self Report
14.
Poult Sci ; 96(12): 4140-4150, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-29053859

ABSTRACT

Aggressive behaviors can affect both animal welfare and productivity. Because the expression of aggressive behaviors is dependent on the quality of the opponent, they reflect relative rather than absolute levels of underlying aggressiveness. This study was aimed to characterize the aggressive responsiveness of photostimulated (14:10 h light:dark photoperiod) adult Japanese quail when interacting with a photocastrated (6:18 h light:dark photoperiod) counterpart in a novel test environment and to assesses interindividual variations. This was based on the assumption that photocastrated birds will not actively provoke an aggressive confrontation. Birds were reared in male-female pairs. Frequencies of behaviors (i.e., pecks, threats, chases, grabs, mounts) were determined during 10 min social interactions in a novel environment. A first experiment evaluated 78 encounters between a photostimulated male or female with either a photocastrated male or female (photocastration of sexually mature birds started at 11 wk of age). High interindividual variability was observed and in general, highly aggressive birds (performing 20 or more aggressive interactions) received little or no aggression from their test counterpart. However, unexpectedly, we also found that 37% and 32% of photocastrated males and females, respectively, performed aggressions toward their photostimulated counterparts, and initiated the aggressive interactions in a similar proportion than photostimulated males. Aggressive photocastrated males did not perform reproductive-type behaviors (i.e., grabs, mounts). Aggressiveness in the photocastrated birds was attributed to their social experience prior to photocastration. Therefore, a second experiment evaluated 106 encounters between a photostimulated male or female and a naive photocastrated male (photocastration started at 4 wk of age, prior to sexual development). Photocastrated males performed no aggressions toward their photostimulated counterparts. Consistently with previous studies, our findings show that naive photocastrated males can be used as a non-aggressive stimulus during a social interaction aimed to assess expression of aggressiveness in photostimulated birds. However, caution should be taken when applying the photocastration protocol considering that prior fighting and sexual experience or other physiological changes related with maturation can interfere during subsequent aggressive testing.


Subject(s)
Aggression/radiation effects , Coturnix/physiology , Photoperiod , Sexual Behavior, Animal/radiation effects , Animals , Orchiectomy
15.
Org Biomol Chem ; 15(37): 7736-7742, 2017 Sep 26.
Article in English | MEDLINE | ID: mdl-28872167

ABSTRACT

An efficient, metal-free synthesis of unusual α-keto γ-amino esters from α-amino acids is achieved by a radical scission-oxidation-addition of silyloxy acrylates procedure, where no purification of the reaction intermediates is needed. This protocol can be applied to the selective modification of the C-terminal position in peptides to give α,γ-hybrids.


Subject(s)
Amino Acids/chemistry , Esters/chemical synthesis , Peptides/chemical synthesis , Esters/chemistry , Molecular Structure , Peptides/chemistry
16.
Poult Sci ; 96(10): 3529-3538, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28938775

ABSTRACT

Injurious pecking (IP) remains one of the major welfare challenges in housing of laying hens worldwide due to the negative consequences it inflicts on animal welfare and economy. One potential solution to reduce IP is the use of dark brooders as the primary heat source during rearing. The objective was to investigate effects of rearing layer chicks with different management strategies and size allowances of dark brooders on IP and production-related traits during rear and lay. Groups of 100 to 103 Isa Warren chicks were reared either with one of 4 brooder types (n = 4 per treatment) or with whole-house heating (control: n = 6). Brooders were either large (54 cm2/chick) or small (72 cm2/chick) and kept at a fixed height or periodically lifted. Plumage and skin condition were scored at age 6, 16, and 28 weeks. The birds were weighed at age one, 16, and 28 weeks. Data on egg production and mortality were registered daily from wk 16 until 27 wk of age. Minor differences between brooder treatments were found but with no clear trend pointing to a specific brooder treatment being superior. In contrast, major differences in IP damage were found between birds reared with or without brooders. Brooder birds had a better plumage condition throughout the experiment (P < 0.001) and fewer wounds during lay (P < 0.001). Mortality due to cannibalism in the brooder treatments tended to be lower during rear (P = 0.066) and was lower during lay (P < 0.001). There was no treatment effect on body weight on d 7 (P = 0.48). Brooder birds laid fewer floor eggs (P < 0.001) and had higher total egg production (P < 0.001). We conclude that an automatic system lifting the brooders regularly may be skipped, and a size allowance of 54 cm2 per chick is sufficient, leaving the design of brooders simple and cheap. Rearing layer chicks with dark brooders can be a successful method of reducing prevalence of IP and floor eggs, whereby mortality is reduced, leading to improved welfare, egg quality, and production performance.


Subject(s)
Aggression , Animal Husbandry/methods , Chickens/physiology , Animal Husbandry/instrumentation , Animal Welfare , Animals , Chickens/growth & development , Female
17.
Sci Total Environ ; 584-585: 882-900, 2017 Apr 15.
Article in English | MEDLINE | ID: mdl-28129908

ABSTRACT

This article describes the High-Elective Resolution Modelling Emission System for Mexico (HERMES-Mex) model, an emission processing tool developed to transform the official Mexico City Metropolitan Area (MCMA) emission inventory into hourly, gridded (up to 1km2) and speciated emissions used to drive mesoscale air quality simulations with the Community Multi-scale Air Quality (CMAQ) model. The methods and ancillary information used for the spatial and temporal disaggregation and speciation of the emissions are presented and discussed. The resulting emission system is evaluated, and a case study on CO, NO2, O3, VOC and PM2.5 concentrations is conducted to demonstrate its applicability. Moreover, resulting traffic emissions from the Mobile Source Emission Factor Model for Mexico (MOBILE6.2-Mexico) and the MOtor Vehicle Emission Simulator for Mexico (MOVES-Mexico) models are integrated in the tool to assess and compare their performance. NOx and VOC total emissions modelled are reduced by 37% and 26% in the MCMA when replacing MOBILE6.2-Mexico for MOVES-Mexico traffic emissions. In terms of air quality, the system composed by the Weather Research and Forecasting model (WRF) coupled with the HERMES-Mex and CMAQ models properly reproduces the pollutant levels and patterns measured in the MCMA. The system's performance clearly improves in urban stations with a strong influence of traffic sources when applying MOVES-Mexico emissions. Despite reducing estimations of modelled precursor emissions, O3 peak averages are increased in the MCMA core urban area (up to 30ppb) when using MOVES-Mexico mobile emissions due to its VOC-limited regime, while concentrations in the surrounding suburban/rural areas decrease or increase depending on the meteorological conditions of the day. The results obtained suggest that the HERMES-Mex model can be used to provide model-ready emissions for air quality modelling in the MCMA.

18.
Poult Sci ; 96(1): 5-13, 2017 Jan 01.
Article in English | MEDLINE | ID: mdl-27591275

ABSTRACT

Quail under short d (SD) reduce their gonadal development, and consequently their cloacal gland (CG) size, aggressiveness, sexual behaviors, and reproductive performance. However, some quail appear nonresponsive to SD inhibition. When male quail were arbitrarily classified according to their CG involution during maximum photoinhibition (5 wk after SD exposure) as either nonresponsive (NR-SD) or responsive (R-SD), NR-SD quail showed intermediate CG volume between R-SD quail and the control quail kept on long d (C-LD). Herein, we evaluate whether NR-SD and R-SD male Japanese quail differ in their social interactions and reproductive performance while under SD; C-LD males were used as fully reproductive control. First, we assessed over 4 consecutive d, brief (5-min) home cage encounters between individually housed C-LD, NR-SD, or R-SD males and an unfamiliar C-LD male visitor. To determine male reproductive capacity, the following wk, males received the visit (10-min) of a mature female over 3 consecutive days. C-LD, NR-SD, and R-SD resident males showed higher aggressiveness than their photostimulated male visitors, respectively, in 100, 64, and 0% of the studied cases and were also able to, respectively, fertilize 100, 100, and 15% of their female visitors. Second, male-female encounters were again repeated 4 wk later to further assess reproductive performance and behavior. Naive C-LD, NR-SD, and R-SD males also were evaluated to assess potential consequences of the previous male-male interactions on the later performance. The number of males performing aggressive pecks towards females showed a C-LD>NR-SD>R-SD pattern. While mounts, CG contacts, and reproductive capacity showed a C-LD = NR-SD>R-SD pattern, copulatory efficiency exhibited an NR-SD>C-LD = R-SD pattern. Sexual behaviors were not modulated by previous male-male brief social interactions. Findings suggest that NR-SD males are able to breed similarly to their C-LD counterparts, which could be considered an indicator of a reduced reproductive dependence on seasonal photoperiod cues. Differences in the expression of aggressions between NR-SD and C-LD males may underlie the observed NR-SD improved copulatory efficiency when interacting with females.


Subject(s)
Cloaca/radiation effects , Photoperiod , Reproduction/radiation effects , Social Behavior , Animals , Coturnix/physiology , Female , Male , Random Allocation , Seasons
19.
Rev. mex. ing. bioméd ; 37(3): 271-285, Sep.-Dec. 2016.
Article in Spanish | LILACS | ID: biblio-961328

ABSTRACT

Resumen En este artículo se presentan los resultados de un proceso de revisión bibliográfica sobre rehabilitación de miembro superior basada en ambientes virtuales. El estudio parte de los siguientes interrogantes sobre el estado actual del conocimiento en el área mencionada: ¿cómo inciden los entornos virtuales frente a la rehabilitación tradicional?, ¿qué métricas de desempeño se han aplicado en la rehabilitación virtual de miembro superior? y ¿qué dispositivos hardware se utilizan en rehabilitación virtual?. Para responder las anteriores preguntas se realizó una búsqueda de artículos científicos en el motor de búsqueda Google Scholar y en las bases de datos PubMed, HINARI, ProQuest y Science Direct. De la revisión realizada se concluyó que pese a la existencia de decenas de índices de desempeño para cuantificar la habilidad motriz, no existen criterios para seleccionar el indice que mejor se adapta a los objetivos de un determinado proceso de rehabilitación.


Abstract This article gives the results of a literature review process about upper limb rehabilitation based on virtual environments. The study borns of the following questions about the current state of knowledge in this subject: how virtual environments influence traditional rehabilitation?, Which performance metrics have been aplied in upper limb virtual rehabilitation? and which hardware devices are used in virtual rehabilitation? To answer the above questions a search for scientific articles was made in the search engine Google Scholar and databases PubMed, HINARI, ProQuest and Science Direct. The conducted review concluded that despite the existence of dozens of performance indicators to quantify the driving ability, there are no criteria to select a better index that best suits the objectives of a rehabilitation process.

20.
J Appl Microbiol ; 121(2): 453-60, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27107399

ABSTRACT

AIM: The aim of this study was to determine the relationship between reactive oxygen species (ROS) production and conidial infectivity in Beauveria bassiana. METHODS AND RESULTS: Beauveria bassiana Bb 882.5 was cultured in solid-state culture (SSC) using rice under three oxygen conditions (21%, or pulses at 16 and 26%). Hydrophobicity was determined using exclusion phase assay. Bioassays with larvae or adults of Tenebrio molitor allowed the measurements of infectivity parameters. A fluorometric method was used for ROS quantification (superoxide and total peroxides). NADPH oxidase (NOX) activity was determined by specific inhibition. Conidial hydrophobicity decreased by O2 pulses. Mortality of larvae was only achieved with conidia harvested from cultures under 21% O2 ; whereas for adult insects, the infectivity parameters deteriorated in conidia obtained after pulses at 16 and 26% O2 . At day 7, ROS production increased after 16 and 26% O2 treatments. NOX activity induced ROS production at early stages of the culture. CONCLUSION: Modification of atmospheric oxygen increases ROS production, reducing conidial quality and infectivity. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study in which conidial infectivity and ROS production in B. bassiana has been related, enhancing the knowledge of the effect of O2 pulses in B. bassiana.


Subject(s)
Beauveria/metabolism , Coleoptera/microbiology , Reactive Oxygen Species/metabolism , Spores, Fungal/pathogenicity , Animals , Beauveria/growth & development , Beauveria/pathogenicity , Larva/microbiology , Pest Control, Biological , Spores, Fungal/growth & development , Spores, Fungal/metabolism , Virulence
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