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2.
Arch Orthop Trauma Surg ; 144(5): 2327-2335, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38653837

RESUMO

BACKGROUND: Despite advancements in total knee arthroplasty (TKA), 10-20% of patients remain dissatisfied after surgery. Improved anteroposterior (AP) stability provided by medial pivot (MP) implants may theoretically lead to higher patient satisfaction. METHODS: AP stability and patient-reported outcome measures (PROMs) at one-year postsurgery were compared between patients who underwent TKA with MP- (n = 121), posterior stabilized (PS; n = 53) and rotating platform (RP; n = 57) implants in a double-blind multicentre randomized controlled trial (Dutch Trial Register: NL6856, 21-02-2018). AP stability was assessed at 30°, 60° and 90° of knee flexion using a KT-2000 arthrometer. PROMs were measured preoperative and one-year postsurgery. RESULTS: MP-TKA provided significant better AP stability at early flexion (30°) compared to PS- and RP-TKA (median [IQR]; 1.79 [1.14-2.77] mm vs. 3.31 [2.51-4.08] mm vs. 2.82 [1.80-4.03] mm, p < 0.001). Additionally, MP-TKA provided significant better AP stability at mid-flexion (60°) compared to PS-TKA (1.75 [1.23-2.36] mm vs. 2.14 [1.49-2.83] mm, p = 0.014). PROM improvements were comparable between implant designs. AP laxity of ≥ 4 mm at early flexion was independently of implant design associated with significantly worse Kujala scores. The incidence of ≥ 4 mm AP laxity at any knee angle was however not significantly different between implant designs. CONCLUSION: MP-, PS- and RP-TKA all provide excellent and comparable results. Although MP-TKA provided better AP stability at early flexion compared to PS- and RP-TKA, this was found to be unrelated to improved PROMs in favour of MP-TKA. More studies focusing on early and mid-flexion performance based differences between MP and other TKA designs are required to confirm our findings. Other non-implant related factors may play a more important role in the performance of TKA and are potentially worthwhile examining.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Medidas de Resultados Relatados pelo Paciente , Humanos , Artroplastia do Joelho/métodos , Artroplastia do Joelho/instrumentação , Método Duplo-Cego , Masculino , Idoso , Feminino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Desenho de Prótese , Articulação do Joelho/cirurgia , Articulação do Joelho/fisiopatologia , Satisfação do Paciente , Instabilidade Articular/cirurgia , Instabilidade Articular/prevenção & controle
3.
Bioresour Technol ; 182: 232-238, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25704095

RESUMO

Recent studies have proposed algal cultivation in urban wastewaters for the dual purpose of waste treatment and bioenergy production from the resulting biomass. This study proposes an enhancement to this approach that integrates cultivation of an acidophilic strain, Galdieria sulphuraria 5587.1, in a closed photobioreactor (PBR); hydrothermal liquefaction (HTL) of the wet algal biomass; and recirculation of the nutrient-rich aqueous product (AP) of HTL to the PBR to achieve higher biomass productivity than that could be achieved with raw wastewater. The premise is that recycling nutrients in the AP can maintain optimal C, N and P levels in the PBR to maximize biomass growth to increase energy returns. Growth studies on the test species validated growth on AP derived from HTL at temperatures from 180 to 300°C. Doubling N and P concentrations over normal levels in wastewater resulted in biomass productivity gains of 20-25% while N and P removal rates also doubled.


Assuntos
Biocombustíveis , Rodófitas/crescimento & desenvolvimento , Águas Residuárias , Biomassa , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Fotobiorreatores , Temperatura , Águas Residuárias/química , Águas Residuárias/microbiologia , Purificação da Água/instrumentação , Purificação da Água/métodos
4.
Bioresour Technol ; 156: 395-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24582952

RESUMO

Nutrient removal from primary wastewater effluent was tested using Galdieria sulphuraria, an acidophilic and moderately thermophilic alga. Biomass yield recorded in this study (27.42g biomass per g nitrogen removed) is higher than the average reported in the literature (25.75g g(-1)) while, the theoretical yield estimated from the empirical molecular formula of algal biomass is 15.8g g(-1). Seven-day removal efficiencies were 88.3% for ammoniacal-nitrogen and 95.5% for phosphates; corresponding removal rates were 4.85 and 1.21mg L(-1)d(-1). Although these rates are lower than the average literature values for other strains (6.36 and 1.34mg L(-1)d(-1), respectively), potential advantages of G. sulphuraria for accomplishing energy-positive nutrient removal are highlighted. Feasibility of growing G. sulphuraria outdoors at densities higher than in high-rate oxidation ponds is also demonstrated.


Assuntos
Adaptação Fisiológica , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Rodófitas/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental , Biomassa , Cidades , Fotobiorreatores , Rodófitas/crescimento & desenvolvimento , Esgotos/química , Temperatura
5.
Talanta ; 101: 440-6, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23158346

RESUMO

A fast near real-time monitoring system for hazardous airborne substances, such as chemical warfare agents (CWA) is presented and limits of detection (LOD) for five CW simulants are determined. A tandem thermal desorber (TTD) continuously collects and pre-concentrates air. The pre-concentrated samples are then separated in a fast gas chromatographic (GC) run of 6.9min. and detected by a time-of-flight mass spectrometer (TOFMS). The GC-TOFMS signals are evaluated using chemometric methods for deconvolution and target identification. The high toxicity of nerve agents requires extremely low detection limits; for some as low as 100 ng/m(3) (10 ppt). The combination of TTD, TOFMS and chemometric data evaluation methods enables the system to fulfill this requirement. Calibration measurements for five different CWA simulants show lower limits of detection in the range of 10 ng/m(3)-60 ng/m(3) (1-11 ppt). In addition, the ability to detect trace concentrations of real CWA is demonstrated with a measurement of 30 pg Sarin on column. Several other real CWA measurements are shown, like sulfur mustard in diesel, lewisite under humid conditions and VX. As part of this work the influence of stationary film thickness on peak tailing of organophosphates is investigated for peak shape optimization.

6.
J Anim Sci ; 90(3): 1056-68, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22079993

RESUMO

This paper compares energy use for different pig production systems in Iowa, a leader in US swine production. Pig production systems include not only the growth and performance of the pigs, but also the supporting infrastructure of pig production. This supporting infrastructure includes swine housing, facility management, feedstuff provision, swine diets, and manure management. Six different facility type × diet formulation × cropping sequence scenarios were modeled and compared. The baseline system examined produces 15,600 pigs annually using confinement facilities and a corn-soybean cropping sequence. Diet formulations for the baseline system were corn-soybean meal diets that included the synthetic AA l-lysine and exogenous phytase. The baseline system represents the majority of current US pork production in the Upper Midwest, where most US swine are produced. This system was found to require 744.6 MJ per 136-kg market pig. An alternative system that uses bedded hoop barns for grow-finish pigs and gestating sows would require 3% less (720.8 MJ) energy per 136-kg market pig. When swine production systems were assessed, diet type and feed ingredient processing were the major influences on energy use, accounting for 61 and 79% of total energy in conventional and hoop barn-based systems, respectively. Improving feed efficiency and better matching the diet formulation with the thermal environment and genetic potential are thus key aspects of reducing energy use by pig production, particularly in a hoop barn-based system. The most energy-intensive aspect of provisioning pig feed is the production of synthetic N for crop production; thus, effectively recycling manure nutrients to cropland is another important avenue for future research. Almost 25% of energy use by a conventional farrow-to-finish pig production system is attributable to operation of the swine buildings. Developing strategies to minimize energy use for heating and ventilation of swine buildings while maintaining pig comfort and performance is a third critical area for future research. The hoop barn-based alternative uses 64% less energy to operate buildings but requires bedding and 2.4% more feed. Current Iowa pig production systems use energy differently but result in similar total energy use. Compared with 1975, current farrow-to-finish systems in Iowa require 80% less energy to produce live market pigs.


Assuntos
Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Suínos , Poluentes Atmosféricos , Ração Animal , Animais , Dieta/veterinária , Efeito Estufa , Iowa , Esterco/análise , Modelos Teóricos , Nitrogênio/química
7.
New Phytol ; 193(3): 755-769, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22092242

RESUMO

• The arbuscular mycorrhizal symbiosis is arguably the most ecologically important eukaryotic symbiosis, yet it is poorly understood at the molecular level. To provide novel insights into the molecular basis of symbiosis-associated traits, we report the first genome-wide analysis of the transcriptome from Glomus intraradices DAOM 197198. • We generated a set of 25,906 nonredundant virtual transcripts (NRVTs) transcribed in germinated spores, extraradical mycelium and symbiotic roots using Sanger and 454 sequencing. NRVTs were used to construct an oligoarray for investigating gene expression. • We identified transcripts coding for the meiotic recombination machinery, as well as meiosis-specific proteins, suggesting that the lack of a known sexual cycle in G. intraradices is not a result of major deletions of genes essential for sexual reproduction and meiosis. Induced expression of genes encoding membrane transporters and small secreted proteins in intraradical mycelium, together with the lack of expression of hydrolytic enzymes acting on plant cell wall polysaccharides, are all features of G. intraradices that are shared with ectomycorrhizal symbionts and obligate biotrophic pathogens. • Our results illuminate the genetic basis of symbiosis-related traits of the most ancient lineage of plant biotrophs, advancing future research on these agriculturally and ecologically important symbionts.


Assuntos
Glomeromycota/genética , Micorrizas/genética , Simbiose/genética , Transcriptoma/genética , Sequência de Bases , Contagem de Colônia Microbiana , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Biblioteca Gênica , Genes Fúngicos/genética , Glomeromycota/crescimento & desenvolvimento , Meiose/genética , Micélio/genética , Micorrizas/crescimento & desenvolvimento , Plantas/microbiologia , Polimorfismo de Nucleotídeo Único/genética , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima/genética
8.
Gene Ther ; 18(12): 1121-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21633392

RESUMO

Despite substantial progress in understanding the cancer-signaling network, effective therapies remain scarce due to insufficient disruption of oncogenic pathways, drug resistance and drug-induced toxicity. This complexity of cancer defines an urgent goal for researchers and clinicians to develop novel therapeutic strategies. The discovery of microRNAs (miRNAs) provides new hope for accomplishing this task. Supported by solid evidence for a critical role in cancer and bolstered by a unique mechanism of action, miRNAs are likely to yield a new class of targeted therapeutics. In contrast to current cancer medicines, miRNA-based therapies function by subtle repression of gene expression on a yet large number of oncogenic factors and are, therefore, anticipated to be highly efficacious. After the completion of target validation for several candidates, the development of therapeutic miRNAs is now moving to a new stage that involves pharmacological drug delivery, preclinical toxicology and regulatory guidelines.


Assuntos
MicroRNAs , Neoplasias/terapia , Avaliação Pré-Clínica de Medicamentos , Marcação de Genes , Guias como Assunto , Humanos , MicroRNAs/administração & dosagem , MicroRNAs/antagonistas & inibidores , MicroRNAs/uso terapêutico , Terapia de Alvo Molecular
9.
J Anim Sci ; 88(3): 1204-12, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19966156

RESUMO

Demand for nonsolar energy and concern about the implications of fossil fuel combustion have encouraged examination of energy use associated with agriculture. The United States is a global leader in pig production, and the United States swine industry is centered in Iowa. Feed is the largest individual input in pig production, but the energy consumption of the Iowa swine feed production chain has yet to be critically examined. This analysis examines nonsolar energy use and resulting 100-yr global warming potential (GWP) associated with the swine feed production chain, beginning with cultivation of crops and concluding with diet formulation. The nonsolar energy use and accompanying 100-yr GWP associated with production of 13 common swine feed ingredients are estimated. Two diet formulation strategies are considered for 4 crop sequence x ingredient choice combinations to generate 8 crop sequence x diet formulation scenarios. The first formulation strategy (simple) does not include synthetic AA or phytase. The second strategy (complex) reduces CP content of the diet by using L-lysine to meet standardized ileal digestibility lysine requirements of pigs and includes the exogenous enzyme phytase. Regardless of crop sequence x diet formulation scenario, including the enzyme phytase is energetically favorable and reduces the potential excretion of P by reducing or removing inorganic P from the complete diet. Including L-lysine reduces the CP content of the diet and requires less nonsolar energy to deliver adequate standardized ileal digestible lysine than simply feeding soybean meal. Replacing soybean meal with full-fat soybeans is not energetically beneficial under Iowa conditions. Swine diets including dried distillers grains with solubles and crude glycerol require approximately 50% more nonsolar energy inputs than corn-soybean meal diets or corn-soybean meal diets including oats. This study provides essential information on cultivation, processing, and manufacture of swine feed ingredients in Iowa that can be coupled with other models to estimate the nonsolar energy use and 100-yr GWP of pig production.


Assuntos
Ração Animal , Criação de Animais Domésticos , Conservação de Recursos Energéticos , Aquecimento Global , Suínos , Agricultura/normas , Ração Animal/normas , Criação de Animais Domésticos/normas , Animais , Avena , Dieta/veterinária , Efeito Estufa , Iowa , Glycine max , Zea mays
10.
IET Syst Biol ; 3(5): 414-28, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21028931

RESUMO

Fungal-plant root associations involve nutrient exchanges, between the partners and the soil, particularly phosphate, that benefit both organisms. Discrete dynamical system (DDS) models are reconstructed to capture gene regulation in the arbuscular mycorrhizae Glomus versiforme-Medicago trunculata root symbiosis. Previously published time-course gene expression data derived from various days post-inoculation were clustered to identify genes co-regulated in mycorrhizal roots. Uncolonised roots grown with high phosphate provide a key nutritional control condition. First-order linear DDS models were created using a data-driven method to fit to the observed gene expression data. The result of the modelling constitutes active gene interactions in the regulatory network of the plant root at 8, 15, 22, 31 and 36 days post-inoculation. These genes are involved in basic metabolism, development, oxidative stress and defense pathways, and show consistent dynamic behaviours in the model. The functions of previously unannotated genes were further elucidated from the developed system maps.


Assuntos
Medicago truncatula/genética , Medicago truncatula/microbiologia , Modelos Genéticos , Micorrizas/genética , Simbiose/genética , Redes Reguladoras de Genes , Genes Fúngicos , Genes de Plantas , Medicago truncatula/metabolismo , Micorrizas/metabolismo , Fosfatos/metabolismo , Raízes de Plantas/microbiologia , Biologia de Sistemas
11.
J Anim Sci ; 86(11): 2962-70, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18599668

RESUMO

The effects of dietary crude glycerin on growth performance, carcass characteristics, meat quality indices, and tissue histology in growing pigs were determined in a 138-d feeding trial. Crude glycerin utilized in the trial contained 84.51% glycerin, 11.95% water, 2.91% sodium chloride, and 0.32% methanol. Eight days postweaning, 96 pigs (48 barrows and 48 gilts, average BW of 7.9 +/- 0.4 kg) were allotted to 24 pens (4 pigs/pen), with sex and BW balanced at the start of the experiment. Dietary treatments were 0, 5, and 10% crude glycerin inclusion in corn-soybean meal-based diets and were randomly assigned to pens. Diets were offered ad libitum in meal form and formulated to be equal in ME, sodium, chloride, and Lys, with other AA balanced on an ideal AA basis. Pigs and feeders were weighed every other week to determine ADG, ADFI, and G:F. At the end of the trial, all pigs were scanned using real-time ultrasound and subsequently slaughtered at a commercial abattoir. Blood samples were collected pretransport and at the time of slaughter for plasma metabolite analysis. In addition, kidney, liver, and eye tissues were collected for subsequent examination for lesions characteristic of methanol toxicity. After an overnight chilling of the carcass, loins were removed for meat quality, sensory evaluation, and fatty acid profile analysis. Pig growth, feed intake, and G:F were not affected by dietary treatment. Dietary treatment did not affect 10th-rib backfat, LM area, percent fat free lean, meat quality, or sensory evaluation. Loin ultimate pH was increased (P = 0.06) in pigs fed the 5 and 10% crude glycerin compared with pigs fed no crude glycerin (5.65 and 5.65 versus 5.57, respectively). Fatty acid profile of the LM was slightly changed by diet with the LM from pigs fed 10% crude glycerin having less linoleic acid (P < 0.01) and more eicosapentaenoic acid (P = 0.02) than pigs fed the 0 or 5% crude glycerin diets. Dietary treatment did not affect blood metabolites or frequency of lesions in the examined tissues. This experiment demonstrated that pigs can be fed up to 10% crude glycerin with no effect on pig performance, carcass composition, meat quality, or lesion scores.


Assuntos
Composição Corporal , Suplementos Nutricionais , Glicerol/administração & dosagem , Carne/normas , Suínos/fisiologia , Animais , Análise Química do Sangue , Ácidos Graxos/química , Feminino , Masculino , Músculo Esquelético/metabolismo , Suínos/crescimento & desenvolvimento
12.
J Anim Sci ; 86(3): 602-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18073284

RESUMO

The apparent DE and ME values of crude glycerol for growing pigs were determined in 5 experiments using crude glycerol (86.95% glycerol) from a biodiesel production facility, which used soybean oil as the initial feedstock. Dietary treatments were 0, 5, or 10% glycerol addition to basal diets in Exp. 1; 0, 5, 10, or 20% glycerol addition to basal diets in Exp. 2; and 0 and 10% crude glycerol addition to the basal diets in Exp. 3, 4, and 5. Each diet was fed twice daily to pigs in individual metabolism crates. After a 10-d adjustment period, a 5-d balance trial was conducted. During the collection period, feces and urine were collected separately after each meal and stored at 0 degrees C until analyses. The GE of each dietary treatment and samples of urine and feces from each pig were determined by isoperibol bomb calorimetry. Digestible energy of the diet was calculated by subtracting fecal energy from the GE in the feed, whereas ME was calculated by subtracting the urinary energy from DE. The DE and ME values of crude glycerol were estimated as the slope of the linear relationship between either DE or ME intake from the experimental diet and feed intake. Among all experiments, the crude glycerol (86.95% glycerol) examined in this study was shown to have a DE of 3,344 +/- 8 kcal/kg and an ME of 3,207 +/- 10 kcal/kg, thereby providing a highly available energy source for growing pigs.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Metabolismo Energético/fisiologia , Glicerol/metabolismo , Suínos/metabolismo , Ração Animal/análise , Animais , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Digestão/fisiologia , Feminino , Glicerol/administração & dosagem , Glicerol/análise , Masculino , Distribuição Aleatória
13.
Poult Sci ; 87(1): 104-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18079458

RESUMO

An experiment was conducted with laying hens to determine the AME(n) value of crude glycerol, a coproduct of biodiesel production. Crude glycerol (87% glycerol, 9% water, 0.03% methanol, 1.26% Na, and 3,625 kcal/kg of gross energy) was obtained from a commercial biodiesel production facility (Ag Processing Inc., Sergeant Bluff, IA). A total of forty-eight 40-wk-old laying hens (Hy-Line W-36) were placed in metabolic cages (2 hens/ cage) and given free access to the experimental diets. A corn and soybean meal-based basal diet (18% CP, 2,875 kcal/kg of AME(n), 4.51% Ca, 0.51% nonphytate P) was formulated with 15% glucose.H(2)O and 1% Celite. Four dietary treatments were created by substituting 0, 5, 10, or 15% crude glycerol for glucose.H(2)O (3,640 kcal/kg of AME(n)). After 7 d of dietary adaptation, excreta were collected twice daily for 3 d, freeze-dried, and analyzed for contents of DM, Kjeldahl N, acid-insoluble ash, and gross energy. Egg production was recorded daily, and eggs were collected on d 7 and 8 of the experiment for calculation of egg mass (egg production x egg weight). Feed consumption was measured over the 10-d experimental period. Egg-production data were analyzed by ANOVA with 4 treatments and 6 replications in a completely randomized experimental design. The AME(n) value of crude glycerol was estimated as the slope of the linear relationship between the inclusion rate of dietary crude glycerol and the glucose-corrected AME(n) value of the experimental diets. No significant treatment effects (P > 0.1) were apparent for egg-production rate (93.0%), egg weight (56.1 g), egg mass (52.2 g/d), or feed consumption (104 g/d). Linear regression analysis (P < 0.001, r(2) = 0.92, n = 24) revealed that the AME(n) value of the crude glycerol used in this study was 3,805 +/- 238 kcal/kg (mean +/- SEM; as-is basis) for laying hens.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/metabolismo , Metabolismo Energético , Glicerol/metabolismo , Oviposição/fisiologia , Ração Animal , Animais , Ovos/análise , Feminino , Modelos Lineares
15.
J Anim Sci ; 85(5): 1311-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17224459

RESUMO

The effects of gestation housing systems on sow and litter performance were evaluated for 2.5 yr in southwest Iowa. Gestation housing system treatments were as follows: 1) individual gestation stalls in a mechanically ventilated confinement building with a partially slatted floor and a manure flush system and 2) group pens with individual feed stalls in deep-bedded, naturally ventilated hoop barns. In all, 957 litters from 353 sows were evaluated. Number of pigs born alive per litter differed for the 2 housing treatments (P = 0.002). Sows gestated in hoop barns gave birth to more live pigs per litter (10.0 +/- 0.2 pigs) than sows gestated in stalls (9.3 +/- 0.2 pigs). Preweaning mortality was not different for the 2 housing treatments (P = 0.70). Cross-fostering was done to equalize litter size within 24 h of birth, which resulted in an equal number of weaned pigs per sow (P = 0.50) regardless of gestation housing treatment. The weaning-to-breeding interval was different (P = 0.01), with sows kept in stalls (4.3 +/- 0.6 d) returning to estrus sooner than sows gestated in hoop barns (6.0 +/- 0.6 d). These results indicate that gestating sows can be housed as groups in deep-bedded hoop barns equipped with individual feeding stalls and will perform comparably to gestating sows housed in confinement systems with individual gestation stalls.


Assuntos
Abrigo para Animais , Suínos/fisiologia , Criação de Animais Domésticos , Animais , Feminino , Gravidez
16.
J Anim Sci ; 84(8): 2269-75, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16864889

RESUMO

After the broad industrialization of the US pork industry, there has been a development of niche markets for export and domestic pork; that is, there is a pork niche market phenomenon. The US pork niche market phenomenon is characterized, and 2 of the major markets are explained in detail. With the Midwest's tradition of a diversified family-based agriculture and record low hog prices of the late 1990s, the conditions were conducive for this phenomenon to develop. Pork niche markets utilize various sales methods including Internet sales, local abattoir sales, direct marketing, farmer networks, and targeting to organized groups. In 2003, there were approximately 35 to 40 active pork niche marketing efforts in Iowa. The Berkshire breed is an example of a swine breed that has had a recent resurgence because of niche markets. Berkshire pork is known for tenderness and excellent quality. Berkshire registrations have increased 4-fold in the last 10 yr. One of the larger niche marketers of "natural pork" is Niman Ranch Pork, which has more than 400 farmer-producers and processes about 2,500 pigs weekly. Many US consumers of pork are interested in issues concerning the environment, food safety, pig welfare, and pig farm ownership and structure. These consumers may be willing to pay more for pork from farmers who are also concerned about these issues. Small- and medium-sized swine farmers are active in pork niche markets. Niche markets claim product differentiation by superior or unique product quality and social attributes. Quality attributes include certain swine breeds, and meat quality, freshness, taste or flavor, and tenderness. Social or credence attributes often are claimed and include freedom from antibiotics and growth promotants; local family farm production; natural, organic, outdoor, or bedded rearing; humane rearing; known origin; environmentally friendly production; and the absence of animal by-products in the feed. Niche pork markets and alternative swine production practices offer an unusual contrast to commodity pork markets and industrial confinement swine production. Because they strive to have these attributes in their product, the niche pork market producers are a distinct clientele group. If niche pork markets continue to flourish, the markets and the producers that supply them will be a viable sector in a diverse US pork industry.


Assuntos
Indústria Alimentícia/economia , Marketing/economia , Carne/economia , Carne/provisão & distribuição , Animais , Carne/normas , Suínos , Estados Unidos
17.
New Phytol ; 168(3): 687-96, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16313650

RESUMO

Nitrogen (N) is known to be transferred from fungus to plant in the arbuscular mycorrhizal (AM) symbiosis, yet its metabolism, storage and transport are poorly understood. In vitro mycorrhizas of Glomus intra-radices and Ri T-DNA-transformed carrot roots were grown in two-compartment Petri dishes. (15)N- and/or (13)C-labeled substrates were supplied to either the fungal compartment or to separate dishes containing uncolonized roots. The levels and labeling of free amino acids (AAs) in the extra-radical mycelium (ERM) in mycorrhizal roots and in uncolonized roots were measured by gas chromatography/mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). Arginine (Arg) was the predominant free AA in the ERM, and almost all Arg molecules became labeled within 3 wk of supplying (15)NH(4) (+) to the fungal compartment. Labeling in Arg represented > 90% of the total (15)N in the free AAs of the ERM. [Guanido-2-(15)N]Arg taken up by the ERM and transported to the intra-radical mycelium (IRM) gave rise to (15)N-labeled AAs. [U-(13)C]Arg added to the fungal compartment did not produce any (13)C labeling of other AAs in the mycorrhizal root. Arg is the major form of N synthesized and stored in the ERM and transported to the IRM. However, NH(4) (+) is the most likely form of N transferred to host cells following its generation from Arg breakdown.


Assuntos
Daucus carota/microbiologia , Micorrizas/metabolismo , Nitrogênio/metabolismo , Aminoácidos/metabolismo , Transporte Biológico , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Simbiose
19.
New Phytol ; 161(2): 330-335, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33873505
20.
Anal Bioanal Chem ; 375(8): 1045-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12733017

RESUMO

Odour emissions from a composting facility were detected by using a quartz crystal microbalance (QCM) sensor array. The array consists of six sensor elements, which were coated with different materials. A series of tests under field conditions showed that considerable sensor frequency changes were detected during the compost-turning period. Using principal component analysis, it was found that more than 90% of the data variance could still be explained by use of two principal components.


Assuntos
Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Indústrias , Odorantes/análise , Solo , Quartzo , Solo/análise
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