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1.
J Dairy Sci ; 107(9): 6460-6473, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38642650

RESUMO

The possibility of inclusion of agro-industrial byproducts in the diet of small ruminants represents both an economic and an environmental strategy for reducing waste management by industries and costs of feeding as well as the impact of livestock farming. Large amounts of wastes from the cocoa industry are produced annually, with a considerable part represented by cocoa bean shells, considered a suitable ingredient to be included in the diet of ruminants within the limits established by European legislation. The aim of this study was to assess the effect of including cocoa bean shells in the diet of dairy sheep on the sensory, volatile, and antioxidant properties of cheese. To this purpose, 20 lactating Comisana ewes were randomly assigned to 2 experimental groups: control (CTRL) and cocoa bean shells (CBS), and received alfalfa hay ad libitum and 800 g of conventional (CTRL) or experimental (CBS) concentrate containing 11.7% CBS to partially replace corn and barley of the CTRL concentrate. Bulk milk collected from each group was used to produce a total of 15 cheeses per group, obtained in 5 different days of cheesemaking (3 cheeses a day per group). After 60 d of aging, each cheese of each experimental group was sampled for the analyses. The results on chemical composition revealed a greater content of monounsaturated fatty acids and an increase in the nutritional indices, suggesting a favorable role of cocoa bean shell dietary inclusion on the nutritive value of cheese. The cheese sensory profile was affected by the cocoa bean shell inclusion, with more pronounced appearance, odor, aroma, and taste attributes in the product. The volatile profile showed only a few significant differences, mainly related to the cheese ripening process, and no differences were found in α-tocopherol contents in cheese fat between the 2 groups. Therefore, the inclusion of coca bean shells in the diet of dairy sheep allowed us to obtain a good-quality cheese, without altering the characteristics associated with the typical profiles of sheep cheese. Furthermore, the use of this byproduct could contribute to decreasing feed costs and waste management, representing a good practice for increasing the sustainability of dairy products.


Assuntos
Ração Animal , Antioxidantes , Cacau , Queijo , Dieta , Leite , Animais , Ovinos , Feminino , Dieta/veterinária , Leite/química , Cacau/química , Lactação
2.
J Dairy Sci ; 106(11): 7515-7529, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641260

RESUMO

Alkaline phosphatase (ALP) is a native raw-milk enzyme used in many countries as the standard assay for rapidly validating the milk pasteurization process. Due to the increased restrictions on the production or import of cheeses produced from unpasteurized milk, ALP activity (<10 mU/g) in cheese was measured as a simple and reliable method to check proper milk pasteurization in cheese for both safety inspection and trading controls. In Sicily, the artisanal cheesemaking of the Protected Denomination of Origin (PDO) semi-hard cheeses made with raw sheep milk, includes the cooking of the curd, after whey separation, in a wooden vat under hot Scotta whey (≥80°C), for 3 to 4 h, and finally is left to cool at ambient temperature. Thus, the temperatures adopted during cheesemaking may inactivate the ALP enzyme. To this purpose, the aim of this study was to demonstrate how different temperatures of Scotta whey (35°C [T35], 60°C [T60], 70°C [T70], 80°C [T80], 90°C [T90], and 100°C [T100]) used during the second cooking of Pecorino cheeses after molding for 3 h, influence the ALP activity in fresh and 3-mo aged cheese, both at core and outside. The results highlight that the rate of reduction of ALP was greater with increasing temperature of the second cooking, in particular for T 80°C curd, indicating that the use of Scotta whey >80°C could be a breakpoint able to reduce the ALP activity to values <10 mU/g. Different effects between the core and the outside portions of the experimental cheeses were found, with a decrease in ALP activity more on the outside than in the core portions, in both fresh and 3-mo aged cheeses, for T80, T90, and T100 treatments. Care must be taken in using ALP to control the use of pasteurized milk in the production of PDO cheeses without considering the cheesemaking processes, such as the second cooking, which could be equal to pasteurization, and an adequate interaction of time and temperature can reduce the ALP activity to values comparable with cheeses produced with pasteurized milk.

3.
J Dairy Sci ; 106(6): 3807-3826, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37164862

RESUMO

This review focused on the historical, technological, and analytical characteristics of ricotta cheese available in the literature. Ricotta cheese is a typical dairy product that originated from Italy, used in the preparation of several traditional dishes, both sweet and salted. The available studies pertaining to ricotta cheese revealed a considerable biodiversity in the production with a large number of varieties produced, whose production varies according to the local uses and customs. The review shows the main chemical and microbial characteristics of the product and also the several parameters that affect the mechanism of the production process and the final characteristics of the product, including the raw materials, the processing methods, the season, the animals' diet, the animals' species, and breeds. Ricotta production can be artisanal or industrial, with differences in the making process. New trends in ricotta cheese production have been developed, with particular attention to the functional effect on human health and the novel technologies applied to extend the shelf-life of the products. Currently, it is not easy to find these new developments in the market, probably related to the cost of production, which is not always bearable by the farms. However, despite the large classification reported and the great interest by the cheese industry, just a few numbers of studies were found for artisanal ricotta productions, which still need to be characterized and studied.


Assuntos
Queijo , Humanos , Animais , Leite/química , Itália
4.
Theor Appl Genet ; 136(4): 72, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36952017

RESUMO

KEY MESSAGE: Here, we provide an updated set of guidelines for naming genes in wheat that has been endorsed by the wheat research community. The last decade has seen a proliferation in genomic resources for wheat, including reference- and pan-genome assemblies with gene annotations, which provide new opportunities to detect, characterise, and describe genes that influence traits of interest. The expansion of genetic information has supported growth of the wheat research community and catalysed strong interest in the genes that control agronomically important traits, such as yield, pathogen resistance, grain quality, and abiotic stress tolerance. To accommodate these developments, we present an updated set of guidelines for gene nomenclature in wheat. These guidelines can be used to describe loci identified based on morphological or phenotypic features or to name genes based on sequence information, such as similarity to genes characterised in other species or the biochemical properties of the encoded protein. The updated guidelines provide a flexible system that is not overly prescriptive but provides structure and a common framework for naming genes in wheat, which may be extended to related cereal species. We propose these guidelines be used henceforth by the wheat research community to facilitate integration of data from independent studies and allow broader and more efficient use of text and data mining approaches, which will ultimately help further accelerate wheat research and breeding.


Assuntos
Melhoramento Vegetal , Triticum , Triticum/genética , Fenótipo , Genes de Plantas , Grão Comestível/genética
5.
Clin Neurophysiol ; 149: 25-31, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36870217

RESUMO

OBJECTIVE: The complexity and delay of the diagnosis of narcolepsy require several diagnostic tests and invasive procedures such as lumbar puncture. Our study aimed to determine the changes in muscle tone (atonia index, AI) at different levels of vigilance during the entire multiple sleep latency test (MSLT) and each nap in people with narcolepsy type 1 (NT1) and 2 (NT2) compared with other hypersomnias and its potential diagnostic value. METHODS: Twenty-nine patients with NT1 (11 M 18F, mean age 34.9 years, SD 16.8) and sixteen with NT2 (10 M 6F, mean age 39 years, SD 11.8) and 20 controls with other hypersomnias (10 M, 10F mean age 45.1 years, SD 15.1) were recruited. AI was evaluated at different levels of vigilance (Wake and REM sleep) in each nap and throughout the MSLT of each group. The validity of AI in identifying patients with narcolepsy (NT1 and NT2) was analyzed using receiver operating characteristic (ROC) curves. RESULTS: AI during wakefulness (WAI) was significantly higher in the narcolepsy groups (NT1 and NT2 p < 0.001) compared to the hypersomniac group. AI during REM sleep (RAI) (p = 0.03) and WAI in nap with sudden onsets of REM sleep periods (SOREMP) (p = 0.001) were lower in NT1 than in NT2. The ROC curves showed high AUC values for WAI (NT1 0.88; Best Cut-off > 0.57, Sensitivity 79.3 % Specificity 90 %; NT2 0.89 Best Cut-off > 0.67 Sensitivity 87.5 % Specificity 95 %; NT1 and NT2 0.88 Best Cut-off > 0.57 Sensitivity 82.2 % Specificity 90 %) in discriminating subjects suffering from other hypersomnias. RAI and WAI in nap with SOREMP showed a poor AUC value (RAI AUC: 0.7 Best cutoff 0.7 Sensitivity 50 % Specificity 87.5 %; WAI in nap before SOREMP AUC: 0.66, Best cut-off < 0.82 sensitivity 61.9 % and specificity 67.35 %) differentiating NT1 and NT2. CONCLUSIONS: WAI may represent an encouraging electrophysiological marker of narcolepsy and suggests a vulnerable tendency to dissociative wake / sleep dysregulation lacking in other forms of hypersomnia. SIGNIFICANCE: AI during wakefulness may help distinguish between narcolepsy and other hypersomnias.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Narcolepsia , Humanos , Adulto , Pessoa de Meia-Idade , Latência do Sono/fisiologia , Narcolepsia/diagnóstico , Polissonografia/métodos , Músculos
6.
JDS Commun ; 4(1): 5-8, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36713127

RESUMO

Ricotta cheese is an Italian dairy product obtained by heat-coagulation of the proteins in whey, resulting from cheese production. The homogenization method applied to collect ricotta cheese samples could affect the total solids (TS) contents of the products. The aim of this study was to determine the effects of 5 different homogenization methods of the samples collection applied for the accuracy in TS determination in ricotta cheese, including un-homogenized method (UNH), un-homogenized combined with the Ultra-Turrax (IKA-Werke GmbH & Co. KG) method (UNH-UTX), spoon-homogenized method (SPN), spoon-homogenized combined with Ultra-Turrax method (SPN-UTX), and Ultra-Turrax homogenized method (UTX). The repeatability and the standard deviation of repeatability are indicators of agreement between repeated measures for TS contents. Results reported that UNH ricotta cheese samples showed large variation in TS content with values ranging from 18.31% to 25.85% and a standard deviation of repeatability higher than 1%; SPN samples showed repeatability values higher than 0.35% and standard deviation of repeatability ranged until 1.36%, suggesting large variability even in this case; the Ultra-Turrax homogenization reported repeatability values lower than 0.1% and standard deviation of repeatability lower than 0.05%, indicating that this method provides repeatable measurements that may reduce the sources of uncertainty in TS determination.

8.
Animal ; 16(9): 100624, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36049262

RESUMO

Although it is still most common to rear dairy calves separately from adult cattle, the interest in prolonged contact between dairy calves and lactating cows during early life is increasing. Previous research has documented positive effects of cow-calf contact (CCC) on for example early calf growth and udder health of suckled cows, but also negative effects such as increased separation distress and reduced weight gains after weaning. The aim of this study was to use information from European farms with prolonged cow-calf contact to identify innovative solutions to common challenges for CCC farms. Commercial dairy farms that kept calves with adult lactating cows for seven days or more after birth were invited to participate, and interviews were performed with 104 farmers from six countries. During interviews, information about farm management, calf rearing, farmers' perception of animal health on their farm, and farmers' drivers and barriers for implementing CCC were collected. We found that CCC was practised in a large variety of housing and management systems, and that calves could be reared together with their dam, with foster cows, or using a combination of the two. The contact period varied considerably (7-305 days) between farms and about 25% of the farms manually milk fed the calves during parts of the milk feeding period. Daily contact time varied between farms, from 30 minutes per day to permanent contact except at milking. Behaviours indicative of separation distress, most commonly vocalisation in cows and calves, were reported by 87% of the farmers. Strategies to alleviate separation distress, for example simultaneous gradual weaning and separation, were used on some farms. Building constraints were most often mentioned as a barrier for implementing CCC. Our findings suggest that CCC is practised in a variety of commonly used husbandry systems. Reported challenges were primarily related to weaning and separation, and to building constraints; these aspects should be areas of future research.


Assuntos
Indústria de Laticínios , Lactação , Animais , Bovinos , Estudos Transversais , Fazendas , Feminino , Leite , Desmame
9.
J Dairy Sci ; 105(11): 8609-8620, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36175229

RESUMO

The aim of the present study was to assess the dietary supplementation of tannins to grazing dairy cows in 2 seasons characterized by a good quality pasture (spring) or a poor-quality pasture (summer). The effects of dietary tannins were assessed on plasma antioxidant status and cytokines profile and on the antioxidant properties of cheese and cheese in vitro digestates. Fourteen lactating dairy cows were divided into 2 homogeneous groups (n = 7): a control group (CON), and an experimental group (TAN) receiving 150 g/head per day of tannins supplementation. The experiment was performed twice, in spring and in summer. The animals were free to graze on spontaneous pasture (spring) or on dry stubble (summer). Blood was sampled at the beginning (d 0), at the midpoint (d 11), and at the end (d 22) of the trial. Individual cheese was produced before the beginning (d -1) and at the end (d 22) of the trial from the milk collected from each cow. On blood plasma, the reactive oxygen metabolites (ROM), biological antioxidant potential (BAP), nonesterified fatty acids quantification, and cytokines profile in terms of IL-10, IL-8, IL-1ß, and IFN-γ were determined. Data on ROM demonstrated that tannins supplementation lowered oxidative stress both in spring and in summer. Accordingly, TAN diet increased BAP levels compared with the CON during summer trial. Thus, feeding tannins resulted in lower ratio between ROM and BAP (oxidative stress index) in both spring and summer. Cytokines' profile showed lower IL-1ß values in TAN group at d 22 during spring season, with a concomitant higher IL-10 level, during summer season. Moreover, TAN group had a lower level of IFN-γ in plasma than CON group, both in spring and in summer. On cheese samples, the in vitro digestion was performed and on cheese and cheese digestates (gastric and intestinal digestate) the free radical scavenging antioxidant activity was evaluated. The intestinal digestate fraction registered the highest antioxidant activity compared with cheese and gastric digestate, in both spring and summer seasons. Furthermore, an improvement of the antioxidant property of cheese and cheese digestates was found. Present data demonstrated that tannins supplementation contributed to reduce the oxidative stress of lactating dairy cows and showed an increase of anti-inflammatory cytokines ratio.


Assuntos
Ração Animal , Queijo , Taninos , Animais , Bovinos , Feminino , Ração Animal/análise , Antioxidantes/metabolismo , Queijo/análise , Dieta/veterinária , Ácidos Graxos não Esterificados/metabolismo , Interleucina-10/metabolismo , Interleucina-8/metabolismo , Lactação , Leite/metabolismo , Estresse Oxidativo , Oxigênio/metabolismo , Plasma , Estações do Ano , Taninos/administração & dosagem
10.
Sci Rep ; 11(1): 19654, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608216

RESUMO

Extensive farming systems are characterized by seasons with different diet quality along the year, as pasture availability is strictly depending on climatic conditions. A number of problems for cattle may occur in each season. Tannins are natural polyphenolic compounds that can be integrated in cows' diet to overcome these seasonal problems, but little is known about their effect on milk quality according to the season. This study was designed to assess the effects of 150 g/head × day of tannin extract supplementation on proximate composition, urea, colour, cheesemaking aptitude, antioxidant capacity, and fatty acid (FA) profile of cow milk, measured during the wet season (WS) and the dry season (DS) of Mediterranean climate. In WS, dietary tannins had marginal effect on milk quality. Conversely, in DS, the milk from cows eating tannins showed 10% lower urea and slight improvement in antioxidant capacity, measured with FRAP and TEAC assays. Also, tannin extract supplementation in DS reduced branched-chain FA concentration, C18:1 t10 to C18:1 t11 ratio and rumenic to linoleic acid ratio. Tannins effect on rumen metabolism was enhanced in the season in which green herbage was not available, probably because of the low protein content, and high acid detergent fibre and lignin contents in diet. Thus, the integration of tannin in the diet should be adapted to the season. This could have practical implications for a more conscious use of tannin-rich extracts, and other tannin sources such as agro-industrial by-products and forages.


Assuntos
Ração Animal , Suplementos Nutricionais , Leite/normas , Estações do Ano , Taninos , Animais , Bovinos , Feminino , Qualidade dos Alimentos , Valor Nutritivo , Taninos/administração & dosagem
11.
J Dairy Sci ; 104(9): 9543-9555, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34127270

RESUMO

The aim of the present study was to compare the effect of dietary tannins on cow cheese quality in 2 different grazing seasons in the Mediterranean. Two experiments were performed on 14 dairy cows reared in an extensive system. The first experiment took place in the wet season (WS), and the second experiment took place in the dry season (DS). In the WS and DS experiments, cows freely grazed green pasture or dry stubbles, respectively, and the diet was supplemented with pelleted concentrate and hay. In both experiments, the cows were divided into 2 balanced groups: a control group and a group (TAN) receiving 150 g of tannin extract/head per day. After 23 d of dietary treatment, individual milk was collected, processed into individual cheeses, and aged 25 d. Milk was analyzed for chemical composition, color parameters, and cheesemaking aptitude (laboratory cheese yield and milk coagulation properties). Cheese was analyzed for chemical composition, proteolysis, color parameters, rheological parameters, fatty acid profile, and odor-active volatile compounds. Data from the WS and DS experiments were statistically analyzed separately with an analysis of covariance model. In the WS experiment, dietary tannin supplementation had no effect on milk and cheese parameters except for a reduced concentration of 2-heptanone in cheese. In the DS experiment, TAN milk showed lower urea N, and TAN cheese had lower C18:1 trans-10 concentration and n-6:n-3 polyunsaturated fatty acid ratio compared with the control group. These differences are likely due to the effect of tannins on rumen N metabolism and fatty acid biohydrogenation. Dietary tannins may differently affect the quality of cheese from Mediterranean grazing cows according to the grazing season. Indeed, tannin bioactivity on rumen metabolism seems to be enhanced during the dry season, when diet is low in protein and rich in acid detergent fiber and lignin. The supplementation dose used in this study (1% of estimated dry matter intake) had no detrimental effects on cheese yield or cheesemaking parameters. Also, it is unlikely that sensorial characteristics would be affected by this kind of dietary tannin supplementation.


Assuntos
Queijo , Taninos , Ração Animal/análise , Animais , Bovinos , Queijo/análise , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Lactação , Leite , Extratos Vegetais , Estações do Ano
12.
Animal ; 15(6): 100243, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34087758

RESUMO

In this study, we hypothesized that dietary cocoa bean shell (CBS) as a partial replacer of human edible cereal grains in the diet of lactating ewes may affect performance and milk and cheese composition. Twenty Comisana lactating ewes allotted into control (CTRL; n = 10) or cocoa (CBS; n = 10) group received alfalfa hay ad libitum and 800 g of conventional (CTRL) or experimental (CBS) concentrate containing 11.7% CBS to partially replace corn and barley of the CTRL concentrate. Milk yield and composition did not differ between groups, and only urea concentration was lower in CBS milk. Dietary CBS increased cheese fat and reduced protein percentage in CBS group. Fatty acid composition of rumen content partially reflected that of the ingested diet, with total saturated fatty acids (SFA), total monounsaturated fatty acids (MUFA), 16:0, 18:0 and 18:1c9 greater in the CBS group. Moreover, all the identified trans- and cis-18:1 isomers were greater in CBS rumen content. Milk and cheese showed a similar fatty acid composition. Total MUFAs were greater in milk and cheese of CBS, mainly due to the proportion of 18:1c9, and conversely, total polyunsaturated fatty acids (PUFA), PUFAn-6 and PUFAn-6-to-PUFAn-3 ratio was greater in CTRL group. Concluding, the inclusion of CBS in the diet of lactating ewes within the limit imposed by the current legislation did not cause detrimental effects on animal performance and milk composition. Interestingly, dietary CBS reduced milk urea concentration probably due to the phenols contained in CBS concentrate. However, our results support that biohydrogenation was weakly impaired by dietary CBS. Finally, CBS negatively affected cheese nutritional characteristics due to lower protein and greater fat content, but improved fat health indexes in milk and cheese.


Assuntos
Queijo , Leite , Animais , Dieta , Suplementos Nutricionais , Ácidos Graxos , Feminino , Lactação , Rúmen , Ovinos
15.
Artigo em Inglês | MEDLINE | ID: mdl-33207370

RESUMO

Crystalline rocks can produce dangerous radiation levels on the basis of their content in radioisotopes. Here, we report radiological data from 10 metamorphic and igneous rock samples collected from the crystalline basement of the Peloritani Mountains (southern Italy). In order to evaluate the radiological properties of these rocks, the gamma radiation and the radon emanation have been measured. Moreover, since some of these rocks are employed as building materials, we assess the potential hazard for population connected to their use. Gamma spectroscopy was used to measure the 226Ra, 232Th and 40K activity concentration, whereas the radon emanation was investigated by using a RAD 7 detector. The results show 226Ra, 232Th and 40K activity concentration values ranging from (17 ± 4) to (56 ± 8) Bq kg-1, (14 ± 3) to (77 ± 14) Bq kg-1 and (167 ± 84) to (1760 ± 242) Bq kg-1, respectively. Values of the annual effective dose equivalent outdoor range from 0.035 to 0.152 mSv y-1, whereas the gamma index is in the range of 0.22-0.98. The 222Rn emanation coefficient and the 222Rn surface exhalation rate vary from (0.63 ± 0.3) to (8.27 ± 1.6)% and from (0.12 ± 0.03) to (2.75 ± 0.17) Bq m-2 h-1, respectively. The indoor radon derived from the building use of these rocks induces an approximate contribution to the annual effective dose ranging from 8 to 176 µSv y-1. All the obtained results suggest that the crystalline rocks from the Peloritani Mountains are not harmful for the residential population, even though they induce annual effective doses due to terrestrial gamma radiation above the worldwide average values. Moreover, their use as building materials does not produce significant health hazards connected to the indoor radon exposure.

16.
Sci Rep ; 9(1): 10250, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308395

RESUMO

The Poaceae constitute a taxon of flowering plants (grasses) that cover almost all Earth's inhabitable range and comprises some of the genera most commonly used for human and animal nutrition. Many of these crops have been sequenced, like rice, Brachypodium, maize and, more recently, wheat. Some important members are still considered orphan crops, lacking a sequenced genome, but having important traits that make them attractive for sequencing. Among these traits is apomixis, clonal reproduction by seeds, present in some members of the Poaceae like Eragrostis curvula. A de novo, high-quality genome assembly and annotation for E. curvula have been obtained by sequencing 602 Mb of a diploid genotype using a strategy that combined long-read length sequencing with chromosome conformation capture. The scaffold N50 for this assembly was 43.41 Mb and the annotation yielded 56,469 genes. The availability of this genome assembly has allowed us to identify regions associated with forage quality and to develop strategies to sequence and assemble the complex tetraploid genotypes which harbor the apomixis control region(s). Understanding and subsequently manipulating the genetic drivers underlying apomixis could revolutionize agriculture.


Assuntos
Eragrostis/genética , Poaceae/genética , Sequência de Bases/genética , Mapeamento Cromossômico/métodos , Evolução Molecular , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Genótipo , Fenótipo , Análise de Sequência/métodos
17.
J Adv Res ; 17: 109-116, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31193259

RESUMO

Neutron scattering applications often require discriminating the elastic contribution from the inelastic contribution. For this purpose, correlation spectroscopy offers an effective tool with both pulsed and continuous neutron sources as well as several advantages: the analysis of the neutron velocity distribution can be carried out with a duty factor of 50%, independently on the resolution value; the best statistical accuracy for spectra where the elastic part encompasses most of the integrated intensity is provided. Depending on the statistical chopper position, correlation analysis can be used for both incoming and outgoing neutron velocity determination. Moreover, the correlation technique is very profitable for investigating weak signals in the presence of high background, which is often the case for small samples. To provide instrument flexibility and versatility, an innovative approach comprising tuning resolution by variable Resolution-Elastic Neutron Scattering (RENS) is proposed, offering further benefits by enabling systematic trading of intensity for resolution and vice versa. This study puts into evidence the advantages offered by the use of statistical chopper and of correlation technique for RENS in choosing the best compromise between resolution and beam intensity.

18.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt B): 3661-3670, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27212689

RESUMO

BACKGROUND: Neutron sources are increasingly employed in a wide range of research fields. For some specific purposes an alternative to existing large-scale neutron scattering facilities, can be offered by the new generation of portable neutron devices. SCOPE OF REVIEW: This review reports an overview for such recently available neutron generators mainly addressed to biophysics applications with specific reference to portable non-stationary neutron generators applied in Neutron Activation Analysis (NAA). MAJOR CONCLUSIONS: The review reports a description of a typical portable neutron generator set-up addressed to biophysics applications. GENERAL SIGNIFICANCE: New generation portable neutron devices, for some specific applications, can constitute an alternative to existing large-scale neutron scattering facilities. Deuterium-Deuterium pulsed neutron sources able to generate 2.5MeV neutrons, with a neutron yield of 1.0×106n/s, a pulse rate of 250Hz to 20kHz and a duty factor varying from 5% to 100%, when combined with solid-state photon detectors, show that this kind of compact devices allow rapid and user-friendly elemental analysis. "This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo".


Assuntos
Biofísica/métodos , Análise de Ativação de Nêutrons/métodos , Nêutrons , Elementos Químicos , Difração de Nêutrons
19.
J Dairy Sci ; 97(4): 2502-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24485675

RESUMO

As part of a larger project aiming to develop management evaluation tools based on results from test-day (TD) models, the objective of this study was to examine the effect of physical composition of total mixed rations (TMR) tested quarterly from March 2006 through December 2008 on milk, fat, and protein yield curves for 25 herds in Ragusa, Sicily. A random regression sire-maternal grandsire model was used to estimate variance components for milk, fat, and protein yields fitted on a full data set, including 241,153 TD records from 9,809 animals in 42 herds recorded from 1995 through 2008. The model included parity, age at calving, year at calving, and stage of pregnancy as fixed effects. Random effects were herd × test date, sire and maternal grandsire additive genetic effect, and permanent environmental effect modeled using third-order Legendre polynomials. Model fitting was carried out using ASREML. Afterward, for the 25 herds involved in the study, 9 particle size classes were defined based on the proportions of TMR particles on the top (19-mm) and middle (8-mm) screen of the Penn State Particle Separator. Subsequently, the model with estimated variance components was used to examine the influence of TMR particle size class on milk, fat, and protein yield curves. An interaction was included with the particle size class and days in milk. The effect of the TMR particle size class was modeled using a ninth-order Legendre polynomial. Lactation curves were predicted from the model while controlling for TMR chemical composition (crude protein content of 15.5%, neutral detergent fiber of 40.7%, and starch of 19.7% for all classes), to have pure estimates of particle distribution not confounded by nutrient content of TMR. We found little effect of class of particle proportions on milk yield and fat yield curves. Protein yield was greater for sieve classes with 10.4 to 17.4% of TMR particles retained on the top (19-mm) sieve. Optimal distributions different from those recommended may reflect regional differences based on climate and types and quality of forages fed.


Assuntos
Ração Animal , Bovinos/fisiologia , Lactação/fisiologia , Leite/química , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Indústria de Laticínios , Fibras na Dieta , Gorduras/análise , Feminino , Itália , Leite/metabolismo , Proteínas do Leite/análise , Tamanho da Partícula , Gravidez
20.
J Dairy Sci ; 97(1): 543-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24210484

RESUMO

This study was performed to evaluate α-tocopherol and ß-carotene contents of pasture milk under ordinary Sicilian farming conditions. Fourteen dairy farms were allocated into 2 balanced groups on the basis of cultivated (CULT) or spontaneous (SPO) pasture type feeding. Bulk milk per farm was collected 4 times from February through April at 3-wk intervals. Pasture botanical and diet composition, diet nutritional quality, milk yield and composition were estimated each time. Pasture intake levels were calculated based on feed analyses, hay and concentrate amounts fed, and milk yield and chemical composition. According to pasture intake, the farms were split into low pasture intake (LPI; <29.5% of dry matter) and high pasture intake (HPI; >29.5% of dry matter) groups. Milk samples per farm were analyzed for α-tocopherol and ß-carotene contents by HPLC. The SPO group had higher levels of α-tocopherol and ß-carotene in milk (0.7 and 0.3 mg/L, respectively) and milk fat (19.0 and 7.5 mg/kg fat, respectively) compared with the CULT group in milk (0.5 and 0.2 mg/L, respectively) and milk fat (14.6 and 4.9 mg/kg, respectively). High pasture intake compared with LPI increased α-tocopherol in milk fat (18.0 and 16.0 mg/kg of fat, respectively). However, only in the SPO (not in CULT), HPI compared with LPI increased milk α-tocopherol (0.8 vs. 0.6 mg/L, respectively), milk ß-carotene (0.3 vs. 0.2 mg/L, respectively), and milk fat ß-carotene (8.4 vs. 6.6 mg/kg, respectively). Results may be related to the different botanical composition of the respective pasture types and pasture intake. Spontaneous pasture compared with CULT contained a higher mass proportion of Asteraceae, Fabaceae, Cruciferae, Euphorbiaceae, and Malvaceae plants. Milk and milk fat α-tocopherol levels were higher on test-days (TD)-1, TD-2, and TD-4 compared with TD-3. For HPI farms, milk fat ß-carotene content was higher on the first 2 TD compared with the last 2 TD. These differences could be related to plant biological stage. On Sicilian dairy farms, the highest milk α-tocopherol and ß-carotene contents may be obtained feeding high levels of SPO pasture in the spring.


Assuntos
Bovinos/fisiologia , Leite/química , alfa-Tocoferol/análise , beta Caroteno/análise , Ração Animal , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Sicília , beta Caroteno/metabolismo
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