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1.
Artículo en Inglés | MEDLINE | ID: mdl-38530791

RESUMEN

OBJECTIVES: The European Alliance of Associations for Rheumatology (EULAR) supports the use of nailfold videocapillaroscopy (NVC) to identify disease patterns (DPs) associated with systemic sclerosis (SSc) and Raynaud's phenomenon (RP). Recently, EULAR proposed an easy-to-manage procedure, a so-called Fast Track algorithm, to differentiate SSc from non-SSc patterns in NVC specimens. However, subjectivity among capillaroscopists remains a limitation. Our aim was to perform a software-based analysis of NVC peculiarities in a cohort of samples from SSc and RP patients and, subsequently, build a Fast Track-inspired algorithm to identify DPs without the constraint of interobserver variability. METHODS: NVCs were examined by 9 capillaroscopists. Those NVCs whose DPs were consensually agreed (≥2 out of 3 interobservers) were subsequently analysed with an in-house developed software. Each variable's results were grouped according to the consensually agreed DPs in order to identify useful hallmarks to categorise them. RESULTS: Eight-hundred and fifty-one NVCs (21 957 images) whose DPs had been consensually agreed were software-analysed. Appropriate cut-offs set in capillary density and percentage of abnormal and giant capillaries, tortuosities and hemorrhages allowed DP categorization and the development of the CAPI-Score algorithm. This consisted of 4 rules: Rule 1, SSc vs non-SSc, accuracy 0.88; Rules 2 and 3, SSc-early vs SSc-active vs SSc-late, accuracy 0.82; Rule 4, non-SSc normal vs non-SSc non-specific, accuracy 0.73. Accuracy improved when the analysis was limited to NVCs whose DPs had achieved full consensus among interobservers. CONCLUSIONS: The CAPI-Score algorithm may become a useful tool to assign DPs by overcoming the limitations of subjectivity.

2.
J Phys Chem A ; 128(28): 5541-5547, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38981043

RESUMEN

Broadband microwave spectra of N-ethyl maleimide (NEM) and N-ethyl succinimide (NES) have been recorded using chirped pulse Fourier transform microwave spectroscopy in the Ka-band (26.5-40 GHz). The spectra for both molecules were fit to a Watson A-reduced Hamiltonian in the Ir representation to obtain best fit experimental rotational constants (NEM: A0 = 2143.1988(29), B0 = 1868.7333(22), C0 = 1082.98458(36); NES: A0 = 2061.47756(14), B0 = 1791.73517(12), C0 = 1050.31263(11)), centrifugal distortion constants, and nuclear quadrupole coupling constants. While the heavy atoms of the five-membered ring of both molecules are planar, the ethyl chain has its terminal methyl group perpendicular to the ring. Along the relaxed potential energy curve for the ethyl dihedral angle (θ1 = C(6)-C(5)-N-C(4)), the ethyl group experiences significant steric strain when it is in the plane of the ring, associated with the interaction of the ethyl group with the two carbonyl oxygens. This leads to calculated barriers of θ1 = 1469 cm-1 and θ1 = 1680 cm-1 in N-ethyl maleimide and N-ethyl succinimide, respectively.

3.
Mikrochim Acta ; 190(4): 160, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36973585

RESUMEN

Two colorimetric nanostructured sensor phases (Color-NSPs) for the determination of low concentrations of acid vapors in the atmosphere of paper storage rooms have been designed and characterized. The acid vapor determination is based on the color change that occurs in polyaniline (PANI) in the presence of acids when it goes from its emeraldine base form (blue) to its emeraldine salt form (green). To synthesize the Color-NSPs, two methods have been used, a one-step method performed by grafting polyaniline onto a cellulose membrane (Cellu-PANI) and a two-step method in which in the first step, polyaniline is grafted onto the surface of polymeric nanoparticles (NPs-PANI), and in a second step, NPs-PANI are immobilized into the pores of a nylon membrane (Nylon-NPs PANI). The response of the sensors versus acid vapor was measured by color coordinates with a photographic camera. A linear response range from 1 ppmv to 7 ppmv was found for both sensors, and the detection limits were 0.95 ppmv (1.2 % RSD) and 0.40 ppmv (0.8 % RSD) for Cellu-PANI and Nylon-NPs PANI, respectively. In addition, both sensors showed complete reversibility and a short exposition time (5 min). The potential applicability of the Color-NSPs in the control of the exposure of paper heritage collections to outdoor- and indoor-generated gaseous pollutants was demonstrated by determining acid vapors in museums. The method was validated with an external reference method; the paired test was applied, and p-values greater than 5% were obtained, indicating an excellent correlation and showing that the Color-NSPs reported are simple, fast, and an economical alternative to control and protect cultural heritage materials in indoor environments.

4.
Phys Rev Lett ; 128(17): 173001, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35570421

RESUMEN

We here report on a quantitative study of enantiomer-specific state transfer, performed in a pulsed, supersonic molecular beam. The chiral molecule 1-indanol is cooled to low rotational temperatures (1-2 K) and a selected rotational level in the electronic and vibrational ground state of the most abundant conformer is depleted via optical pumping on the S_{1}←S_{0} transition. Further downstream, three consecutive microwave pulses with mutually perpendicular polarizations and with a well-defined duration and phase are applied. The population in the originally depleted rotational level is subsequently monitored via laser-induced fluorescence detection. This scheme enables a quantitative comparison of experiment and theory for the transfer efficiency in what is the simplest enantiomer-specific state transfer triangle for any chiral molecule, that is, the one involving the absolute ground state level, |J_{K_{a}K_{c}}⟩=|0_{00}⟩. Moreover, this scheme improves the enantiomer enrichment by over an order of magnitude compared to previous works. Starting with a racemic mixture, a straightforward extension of this scheme allows one to create a molecular beam with an enantiomer-pure rotational level, holding great prospects for future spectroscopic and scattering studies.


Asunto(s)
Vibración , Estereoisomerismo
5.
Chemphyschem ; 23(6): e202100808, 2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35102679

RESUMEN

Broadband microwave spectra were recorded over the 2-18 GHz frequency range for a series of four model aromatic components of lignin; namely, guaiacol (ortho-methoxy phenol, G), syringol (2,6-dimethoxy phenol, S), 4-methyl guaiacol (MG), and 4-vinyl guaiacol (VG), under jet-cooled conditions in the gas phase. Using a combination of 13 C isotopic data and electronic structure calculations, distortions of the phenyl ring by the substituents on the ring are identified. In all four molecules, the rC(1)-C(6) bond between the two substituted C-atoms lengthens, leading to clear bond alternation that reflects an increase in the phenyl ring resonance structure with double bonds at rC(1)-C(2) , rC(3)-C(4) and rC(5)-C(6) . Syringol, with its symmetric methoxy substituents, possesses a microwave spectrum with tunneling doublets in the a-type transitions associated with H-atom tunneling. These splittings were fit to determine a barrier to hindered rotation of the OH group of 1975 cm-1 , a value nearly 50 % greater than that in phenol, due to the presence of the intramolecular OH⋅⋅⋅OCH3 H-bonds at the two equivalent planar geometries. In 4-methyl guaiacol, methyl rotor splittings are observed and used to confirm and refine an earlier measurement of the three-fold barrier V3 =67 cm-1 . Finally, 4-vinyl guaiacol shows transitions due to two conformers differing in the relative orientations of the vinyl and OH groups.


Asunto(s)
Lignina , Fenoles , Microondas , Fenoles/química , Rotación
6.
BMC Vet Res ; 18(1): 58, 2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35086534

RESUMEN

BACKGROUND: Caprine tuberculosis (TB) is a zoonosis caused by members of the Mycobacterium tuberculosis complex (MTBC). Caprine TB control and eradication programmes have traditionally been based on intradermal tuberculin tests and slaughterhouse surveillance. However, this strategy has limitations in terms of sensitivity and specificity. Different factors may affect the performance of the TB diagnostic tests used in goats and, subsequently, the detection of TB-infected animals. In the present study, the effect of two of the factors that may affect the performance of the techniques used to diagnose TB in goats, the topical administration of corticosteroids and a recent pre-sensitisation with tuberculin, was analysed. METHODS: The animals (n = 151) were distributed into three groups: (1) a group topically treated with corticosteroids 48 h after intradermal tuberculin tests (n = 53); (2) a group pre-sensitised with bovine and avian purified protein derivatives (PPDs) 3 days before the intradermal tuberculin test used for TB diagnosis (n = 48); and (3) a control group (n = 50). All the animals were tested using single and comparative intradermal tuberculin (SIT and CIT, respectively) tests, an interferon-gamma release assay (IGRA) and a P22 ELISA. RESULTS: The number of SIT test reactors was significantly lower in the group treated with corticosteroids when compared to the pre-sensitised (p < 0.001) and control (p = 0.036) groups. In contrast, pre-sensitisation with bovine and avian PPDs did not cause a significant reduction in the number of SIT and CIT test reactors compared with the control group. In fact, a higher number of reactors was observed after the prior tuberculin injection in the pre-sensitised group (p > 0.05). No significant effect was observed on IGRA and P22 ELISA due to corticosteroids administration. Nevertheless, a previous PPD injection affected the IGRA performance in some groups. CONCLUSIONS: The application of topical corticosteroid 24 h before reading the SIT and CIT tests can reduce the increase in skin fold thickness and subsequently significantly decrease the number of positive reactors. Corticosteroids used can be detected in hair samples. A previous pre-sensitisation with bovine and avian PPDs does not lead to a significant reduction in the number of intradermal tests reactors. These results are valuable in order to improve diagnosis of caprine TB and detect fraudulent activities in the context of eradication programs.


Asunto(s)
Enfermedades de los Bovinos , Enfermedades de las Cabras , Tuberculosis , Administración Tópica , Corticoesteroides/uso terapéutico , Animales , Bovinos , Enfermedades de las Cabras/diagnóstico , Enfermedades de las Cabras/tratamiento farmacológico , Enfermedades de las Cabras/epidemiología , Cabras , Sensibilidad y Especificidad , Tuberculina , Prueba de Tuberculina/veterinaria , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/veterinaria
7.
BMC Plant Biol ; 21(1): 586, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34886809

RESUMEN

BACKGROUND: A mannitol stress treatment and a subsequent application of n-butanol, known as a microtubule-disrupting agent, enhance microspore embryogenesis (ME) induction and plant regeneration in bread wheat. To characterize changes in cortical (CMT) and endoplasmic (EMT) microtubules organization and dynamics, associated with ME induction treatments, immunocytochemistry studies complemented by confocal laser scanning microscopy (CLSM) were accomplished. This technique has allowed us to perform advanced 3- and 4D studies of MT architecture. The degree of MT fragmentation was examined by the relative fluorescence intensity quantification. RESULTS: In uni-nucleated mannitol-treated microspores, severe CMT and EMT fragmentation occurs, although a complex network of short EMT bundles protected the nucleus. Additional treatment with n-butanol resulted in further depolymerization of both CMT and EMT, simultaneously with the formation of MT aggregates in the perinuclear region. Some aggregates resembled a preprophase band. In addition, a portion of the microspores progressed to the first mitotic division during the treatments. Bi-nucleate pollen-like structures showed a high MT depolymerization after mannitol treatment and numerous EMT bundles around the vegetative and generative nuclei after n-butanol. Interestingly, bi-nucleate symmetric structures showed prominent stabilization of EMT. CONCLUSIONS: Fragmentation and stabilization of microtubules induced by mannitol- and n-butanol lead to new configurations essential for the induction of microspore embryogenesis in bread wheat. These results provide robust insight into MT dynamics during EM induction and open avenues to address newly targeted treatments to induce ME in recalcitrant species.


Asunto(s)
1-Butanol/farmacología , Manitol/farmacología , Microtúbulos/efectos de los fármacos , Polen/efectos de los fármacos , Triticum/efectos de los fármacos , Microscopía Confocal , Microtúbulos/ultraestructura , Desarrollo de la Planta , Triticum/embriología , Triticum/ultraestructura
8.
Phys Chem Chem Phys ; 23(12): 7048-7056, 2021 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-33625420

RESUMEN

We report on rotationally resolved laser induced fluorescence (LIF) and vibrationally resolved resonance-enhanced multiphoton ionization (REMPI) spectroscopy of the chiral molecule 1-indanol. Spectra of the S1← S0 electronic transition are recorded in a jet-cooled, pulsed molecular beam. Using two time-delayed pulsed lasers, the lifetimes of the S1 state of the two most stable conformers, referred to as eq1 and ax2, have been determined. The S1← S0 origin bands of these conformers as well as the transition to a vibrationally excited level in the S1 state of eq1 are recorded with full rotational resolution (25 MHz observed linewidth) by measuring the LIF intensity following excitation with a tuneable, narrowband cw laser. On selected rotationally resolved electronic transitions, Lamb-dips are measured to confirm the Lorentzian lifetime-contribution to the observed lineshapes. The rotationally resolved S1← S0 origin band of a neon-complex of eq1 is measured via LIF as well. The fit of the rotationally resolved LIF spectra of the origin bands to those of an asymmetric rotor yields a standard deviation of about 6 MHz. The resulting spectroscopic parameters are tabulated and compared to the outcome of ab initio calculations. For both conformers as well as for the Ne-eq1 complex, the geometric structures in the S0 and S1 states are discussed. For all systems, the transition dipole moment is mainly along the a-axis, the contributions along the b- and c-axes being about one order of magnitude smaller.

9.
Int Endod J ; 54(3): 413-426, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33107032

RESUMEN

AIM: To evaluate in a laboratory setting the antimicrobial properties and the potential to inhibit biofilm formation of novel remineralizing polymeric nanoparticles (NPs) when applied to dentine surfaces and to ascertain the effect of the functionalization of these NPs with zinc, calcium or doxycycline. METHODOLOGY: The antimicrobial activity and inhibition of biofilm formation of polymeric NPs were analysed on human dentine blocks that were infected with Enterococcus faecalis before or after application of NPs. LIVE/DEAD ® testing under Confocal Laser Scanning Microscopy and bacterial culturing were employed to analyse biofilm biovolume and bacterial viability. Field Emission Scanning Electron Microscopy was also employed to assess biofilm morphology. One-way anova with Welch's correction and post hoc comparison by the Games-Howell test were performed for comparisons between groups. RESULTS: The un-functionalized NPs displayed the greatest antimicrobial activity against E. faecalis biofilms as they provided the lowest biovolume (3865.7 ± 2926.97 µm3 ; P < 0.001) and the highest dead/injured cells percentage (79.93 ± 18.40%; P < 0.001), followed by Dox-NPs (biovolume: 19,041.55 ± 17,638.23 µm3 , dead/injured cells: 45.53 ± 26.50%; P < 0.001). Doxycycline-loaded NPs had the largest values of inhibition of biofilm formation with the lowest biofilm biovolume (8517.65 ± 7055.81 µm3 ; P < 0.001) and a high dead/injured bacterial percentage (68.68 ± 12.50%; P < 0.001). Un-functionalized NPs did not reduce biomass growth (P > 0.05), but attained the largest percentage of compromised cells (93 ± 8.23%; P < 0.001), being able to disrupt biofilm formation. It also produced occlusion of dentinal tubules, potentially interfering with bacterial tubule penetration. CONCLUSIONS: A new generation of bioactive nano-fillers (doxycycline-functionalized polymeric NPs) had antibacterial activity and occluded dentinal tubules. Incorporating these NPs into endodontic sealers may have the potential to enhance the outcome of root canal treatment.


Asunto(s)
Enterococcus faecalis , Nanopartículas , Antibacterianos/farmacología , Biopelículas , Dentina , Doxiciclina/farmacología , Humanos , Microscopía Confocal , Irrigantes del Conducto Radicular
10.
BMC Surg ; 21(1): 243, 2021 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-34006282

RESUMEN

BACKGROUND: Prevention of incisional hernias with a prophylactic mesh in emergency surgery is controversial. The present study aimed to analyze the long-term results of prophylactic mesh used for preventing incisional hernia after emergency midline laparotomies. METHODS: This study was a registered (NCT04578561) retrospective analysis of patients who underwent an emergency midline laparotomy between January 2009 and July 2010 with a follow-up period of longer than 2 years. Long-term outcomes and risk factors for the development of incisional hernias between patients who received a prophylactic reinforcement mesh (Group M) and suture (Group S) were compared. RESULTS: From an initial 266 emergency midline laparotomies, 187 patients were included. The median follow-up time was 64.4 months (SD 35). Both groups had similar characteristics, except for a higher rate of previous operations (62 vs. 43.2%; P = 0.01) and operation due to a revision laparotomy (32.5 vs.13%; P = 0.02) in the M group. During follow-up, 29.9% of patients developed an incisional hernia (Group S 36.6% vs. Group M 14.3%; P = 0.002). Chronic mesh infections were diagnosed in 2 patients, but no mesh explants were needed, and no patient in the M group developed chronic pain. Long-term risk factors for incisional hernia were as follows: smoking (HR = 2.47; 95% CI 1.318-4.624; P = 0.05), contaminated surgery (HR = 2.98; 95% CI 1.142-7.8; P = 0.02), surgical site infection (SSI; HR = 3.83; 95% CI 1.86-7.86; P = 0.001), and no use of prophylactic mesh (HR = 5.09; 95% CI 2.1-12.2; P = 0.001). CONCLUSION: Incidence of incisional hernias after emergency midline laparotomies is high and increases with time. High-risk patients, contaminated surgery, and surgical site infection (SSI) benefit from mesh reinforcement. Prophylactic mesh use is safe and feasible in emergencies with a low long-term complication rate. TRIAL REGISTRATION: NCT04578561. www.clinicaltrials.gov.


Asunto(s)
Hernia Incisional , Laparotomía , Urgencias Médicas , Estudios de Seguimiento , Humanos , Hernia Incisional/epidemiología , Hernia Incisional/etiología , Hernia Incisional/prevención & control , Laparotomía/efectos adversos , Estudios Retrospectivos , Mallas Quirúrgicas
11.
Ann Hematol ; 99(5): 955-962, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32266426

RESUMEN

Hereditary anemias are a group of heterogeneous disorders including hemolytic anemias and hyporegenerative anemias, as congenital dyserythropoietic anemia (CDA). Causative mutations occur in a wide range of genes leading to deficiencies in red cell production, structure, or function. The genetic screening of the main genes is important for timely diagnosis, since routine laboratory tests fail in a percentage of the cases, appropriate treatment decisions, and genetic counseling purposes. A conventional gene-by-gene sequencing approach is expensive and highly time-consuming, due to the genetic complexity of these diseases. To overcome this problem, we customized a targeted sequencing panel covering 35 genes previously associated to red cell disorders. We analyzed 36 patients, and potentially pathogenic variants were identified in 26 cases (72%). Twenty variants were novel. Remarkably, mutations in the SPTB gene (ß-spectrin) were found in 34.6% of the patients with hereditary spherocytosis (HS), suggesting that SPTB is a major HS gene in the Southeast of Brazil. We also identified two cases with dominant HS presenting null mutations in trans with α-LELY in SPTA1 gene. This is the first comprehensive genetic analysis for hereditary anemias in the Brazilian population, contributing to a better understanding of the genetic basis and phenotypic consequences of these rare conditions in our population.


Asunto(s)
Anemia Diseritropoyética Congénita/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Mutación , Espectrina/genética , Esferocitosis Hereditaria/genética , Brasil , Femenino , Humanos , Masculino
12.
J Appl Microbiol ; 128(4): 1015-1024, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31782867

RESUMEN

AIM: The aim of this study was to test the hypothesis that Manuka honey (MH) chelates iron and promotes an iron-limiting environment, which contributes to its antimicrobial activity. METHODS AND RESULTS: Employing a ferrozine-based assay, we observed that MH is an iron chelator that depletes iron from solution. Siderophores are small molecules that bind ferric iron (III) with high affinity and their levels are upregulated by bacteria under iron-limiting conditions. We demonstrated by quantitating siderophore production that Escherichia coli and Pseudomonas aeruginosa treated with MH sub-minimum inhibitory concentrations (sub-MIC) experience an iron-limiting environment and increase siderophore production. In addition, supplementation with ferrous iron (II) significantly increased growth of E. coli, Staphylococcus aureus and P. aeruginosa cultured at their MH MIC above that observed in nonsupplemented controls. By contrast, supplementation with ferric iron (III) significantly increased growth for only E. coli and P. aeruginosa, above their nonsupplemented controls. CONCLUSIONS: Manuka honey chelates iron, thereby generating an iron-limiting environment for E. coli and P. aeruginosa, and to a lesser extent S. aureus, which contributes to its antimicrobial properties. SIGNIFICANCE AND IMPACT OF THE STUDY: Our work demonstrates that MH-induced iron chelation is an antimicrobial mechanism that differentially impacts the bacterial species tested here. Iron chelation affects multiple diverse physiological processes in bacteria and would contribute to the lack of bacterial resistance to MH. Iron metabolism is tightly regulated; bacteria require this essential nutrient for survival, but in excess it is toxic. Additional exploration of MH's iron chelation mechanism will facilitate its future use in mainstream medicine.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Miel , Quelantes del Hierro/farmacología , Hierro/metabolismo , Antibacterianos/metabolismo , Bacterias/clasificación , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Quelantes del Hierro/metabolismo , Pruebas de Sensibilidad Microbiana , Sideróforos/metabolismo , Especificidad de la Especie
14.
World J Surg ; 44(3): 741-748, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31741074

RESUMEN

BACKGROUND: Few data are available about the frequency of incisional hernia in an emergency subcostal laparotomy. Our objective is to analyze the incidence of incisional hernia after emergency subcostal laparotomy and evaluate if prophylactic mesh could help prevent it. METHODS: This study is a monocentric retrospective analysis following STROBE guideline statements of all patients who underwent an emergency subcostal laparotomy between January 2011 and July 2017 in our University Hospital. We compared complications and incidence of incisional hernia between patients who received sutures (Group S; N = 203) and patients with prophylactic onlay mesh (Group M; N = 80). A multivariate risk factor analysis of incisional hernia was performed. An incisional hernia-estimated risk calculator equation was created. RESULTS: A total of 283 patients were analyzed. There were 80 patients in Group M and 203 in Group S. In short-term outcomes, length of surgery (213 ± 115 min vs 165 ± 73.3 min, P = 0.001) and hospital stay (16.4 ± 18.7 vs 11.6 days ± 13.4, P = 0.038) were longer in Group M. Long-term follow-up was conducted in 207 patients with a mean follow-up time of 39.3 ± 23 months. Incisional hernia was detected in 29 (19.1%) patients in Group S but in only two (3.8%) patients in Group M (P = 0.008). In the multivariate analysis, a risk factor analysis included wound infection (4.91 HR (2.12-11.4); P < 0.001), previous hernia repair (2.86 HR (1.24-6.61); P = 0.014), and shock (2.64 HR (1.01-6.93); P = 0.048). CONCLUSIONS: The incidence of incisional hernia after emergency subcostal laparotomy is high. Risk factors are wound infection, shock, and previous hernia surgery. The use of prophylactic mesh augmentation was safe and reduced the incidence of incisional hernia.


Asunto(s)
Hernia Incisional/epidemiología , Laparotomía/efectos adversos , Mallas Quirúrgicas , Anciano , Anciano de 80 o más Años , Urgencias Médicas , Femenino , Humanos , Incidencia , Hernia Incisional/prevención & control , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Técnicas de Sutura
15.
Bull Entomol Res ; 110(2): 270-277, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31495348

RESUMEN

Predation by Engytatus varians (Distant) adults on different development stages of the prey species Bactericera cockerelli (Sulcer) (egg, second, and third nymphal instars), Spodoptera exigua (Hübner) and Spodoptera frugiperda (J. E. Smith) (egg, first, and second larval instars) was evaluated using tomato (Solanum lycopersicum L.) leaflets or plants. These insects are the primary pest of several agriculturally important crops. The influence of E. varians age on the predation capacity was also analysed. Engytatus varians females consumed significantly more B. cockerelli eggs and nymphs than males. Additionally, female predators consumed significantly more second than third instar prey at two predator ages, while males consumed significantly more the second instar than third instar prey at all predator ages. In most of the cases, females also consumed significantly more S. exigua and S. frugiperda eggs than males; however, in terms of larvae consumption, this difference was observed only in some predator ages. Females consumed more the first than second instar S. exigua than males, whereas this behaviour was only observed in males when the predators were 15 and 17 days old. No significant differences were observed in the consumption of first and second instar of S. frugiperda for both sexes of the predators. Predator age did not cause any systematic effects on the predation rates of any prey species. Based on these results, we confirmed that E. varians has potential as a biological control agent for B. cockerelli and also for the Spodoptera species bioassayed.


Asunto(s)
Hemípteros , Conducta Predatoria , Spodoptera , Animales , Femenino , Larva , Masculino , Ninfa , Óvulo
16.
J Dairy Sci ; 103(8): 7451-7461, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32448574

RESUMEN

Objectives were to evaluate the effects of rumen-protected glucose (RPG) supplementation on milk production, post-absorptive metabolism, and inflammatory biomarkers in transition dairy cows. Fifty-two multiparous cows were blocked by previous 305-d mature-equivalent milk (305ME) yield and randomly assigned to 1 of 2 iso-energetic and iso-nitrogenous treatments: (1) control diet (CON; n = 26) or (2) a diet containing RPG (pre-fresh 5.3% of dry matter and 6.0% of dry matter postpartum; n = 26). Cows received their respective dietary treatments from d -21 to 28 relative to calving, and dry matter intake was calculated daily during the same period. Weekly body weight, milk composition, and fecal pH were recorded until 28 d in milk (DIM), and milk yield was recorded through 105 DIM. Blood samples were collected on d -7, 3, 7, 14, and 28 relative to calving. Data were analyzed using repeated measures in the MIXED procedure (SAS Institute Inc., Cary, NC) with previous 305ME as a covariate. Fecal pH was similar between treatments and decreased (0.6 units) postpartum. Dry matter intake pre- and postpartum were unaffected by treatment, as was milk yield during the first 28 or 105 DIM. Milk fat, protein, and lactose concentration were similar for both treatments. Blood urea nitrogen and plasma glucose concentrations were unaffected by treatment; however, results showed increased concentration of circulating insulin (27%), lower nonesterified fatty acids (28%), and lower postpartum ß-hydroxybutyrate (24%) in RPG-fed cows. Overall, circulating lipopolysaccharide-binding protein and haptoglobin did not differ by treatment, but at 7 DIM, RPG-fed cows had decreased lipopolysaccharide-binding protein and haptoglobin concentrations (31 and 27%, respectively) compared with controls. Supplemental RPG improved some biomarkers of post-absorptive energetics and inflammation during the periparturient period, changes primarily characterized by increased insulin and decreased nonesterified fatty acids concentrations, with a concomitant reduction in acute phase proteins without changing milk production and composition.


Asunto(s)
Alimentación Animal , Enfermedades de los Bovinos/sangre , Glucosa/farmacología , Inflamación/veterinaria , Ácido 3-Hidroxibutírico/sangre , Animales , Peso Corporal , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Grasos no Esterificados/sangre , Femenino , Glucosa/metabolismo , Inflamación/sangre , Inflamación/tratamiento farmacológico , Insulina/sangre , Lactancia/efectos de los fármacos , Lactosa/análisis , Lactosa/metabolismo , Leche , Rumen/metabolismo
17.
Nano Lett ; 19(2): 684-691, 2019 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-30669832

RESUMEN

Hot-carriers, that is, charge carriers with an effective temperature higher than that of the lattice, may contribute to the high power conversion efficiency (PCE) shown by perovskite-based solar cells (PSCs), which are now competitive with silicon solar cells. Hot-carriers lose their excess energy in very short times, typically in a few picoseconds after excitation. For this reason, the carrier dynamics occurring on this time scale are extremely important in determining the participation of hot-carriers in the photovoltaic process. However, the stability of PSCs over time still remains an issue that calls for a solution. In this work, we demonstrate that the insertion of graphene flakes into the mesoscopic TiO2 scaffold leads to stable values of carrier temperature. In PSCs aged over 1 week, we indeed observe that in the graphene-free perovskite cells the carrier temperature decreases by about 500 K from 1800 to 1300 K, while the graphene-containing cell shows a reduction of less than 200 K after the same aging time delay. The stability of the carrier temperature reflects the stability of the perovskite nanocrystals embedded in the mesoporous graphene-TiO2 layer. Our results, based on femtosecond transient absorption measurements, show that the insertion of graphene can be beneficial for the design of stable PSCs with the aim of exploiting the hot-carrier contribution to the PCE of the PSCs.

18.
Mol Psychiatry ; 23(1): 94-106, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28948971

RESUMEN

Psychiatric disorders are debilitating diseases, affecting >80 million people worldwide. There are no causal cures for psychiatric disorders and available therapies only treat the symptoms. The etiology of psychiatric disorders is unknown, although it has been speculated to be a combination of environmental, stress and genetic factors. One of the neurotransmitter systems implicated in the biology of psychiatric disorders is the purinergic system. In this review, we performed a comprehensive search of the literature about the role and function of the purinergic system in the development and predisposition to psychiatric disorders, with a focus on depression, schizophrenia, bipolar disorder, autism, anxiety and attention deficit/hyperactivity disorder. We also describe how therapeutics used for psychiatric disorders act on the purinergic system.


Asunto(s)
Trastornos Mentales/metabolismo , Purinas/metabolismo , Receptores Purinérgicos/metabolismo , Animales , Causalidad , Humanos , Trastornos Mentales/etiología , Trastornos Mentales/genética , Receptores Purinérgicos/genética
19.
J Chem Phys ; 151(8): 084312, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31470710

RESUMEN

In the weak-field limit in which microwave spectroscopy is typically carried out, an application of a single-frequency pulse that is resonant with a molecular transition will create a coherence between the pair of states involved in the rotational transition, producing a free-induction decay (FID) that, after Fourier transform, produces a molecular signal at that same resonance frequency. With the advent of chirped-pulse Fourier transform microwave methods, the high-powered amplifiers needed to produce broadband microwave spectra also open up other experiments that probe the molecular response in the high-field regime. This paper describes a series of experiments involving resonant frequency pulses interrogating jet-cooled molecules under conditions of sufficient power to Rabi oscillate the two-state system through many Rabi cycles. The Fourier-transformed FID shows coherent signal not only at the applied resonant frequency but also at a series of transitions initially connected to the original one by sharing an upper or lower level with it. As the duration of the single-frequency excitation is increased from 250 to 1500 ns, the number of observed off-resonant, but dipole-allowed, molecular coherences grow. The phenomenon is quite general, having been demonstrated in Z-phenylvinylnitrile, E-phenylvinylnitrile (E-PVN), benzonitrile, guaiacol, and 4-pentynenitrile. In E-PVN, the highest power/longest pulse duration, coherent signal is also present at energetically nearby but not directly connected transitions. Even in molecular samples containing more than one independent species, only transitions due to the single species responsible for the original resonant transition are present. We develop a time-dependent model of the molecular/photon system and use it in conjunction with the experiment to test possible sources of the phenomenon.

20.
J Environ Manage ; 247: 439-448, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31254759

RESUMEN

Due to lower-cost energy supplies elsewhere, Europe needs resource efficient technologies to safeguard the competitiveness of its energy-intensive industries. The technical feasibility of the CCU value chain components (carbon capture, transportation and utilization) has been widely studied in literature. However infrastructural, regulatory and business strategic issues have received less attention. A review of the relevant policies (e.g. European Emissions Trading Scheme, Renewable Fuels and Waste Directives) has been performed. Stakeholder engagement and the stakeholder influence mapping was used to examine potential climate change, circular economy, renewable energy and regional industrial development policies that can support CO2 utilization value chains. The main contribution of the paper is to outline potential benefits of policies to foster the production and uptake of CO2-derived products such as methanol, polyurethane and mineral construction aggregates. Another outcome is to illustrate the role of key policy-making stakeholders in assessing the suitability of current statutes and the impact of potential changes. An important finding was that the development of connectivity infrastructure is a key missing enabler and more attention to policy on infrastructure is required. Finally, the work examines the justification for a CO2 Utilization Directive, comparable to the Carbon Capture and Storage Directive, but considering the current complexity of the European Union (EU) policy landscape.


Asunto(s)
Dióxido de Carbono , Cambio Climático , Europa (Continente) , Industrias , Energía Renovable
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