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排序方式: 共有1159条查询结果,搜索用时 31 毫秒
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In recent decades India has achieved one of the fastest economic growth rates in the world, yet its progress against both child and adult undernutrition has been sluggish at best. While this Indian variant of the so-called Asian enigma presents many puzzles, one of the puzzles pertains to agriculture’s role. Many researchers and policymakers have high expectations of agriculture’s potential to reduce undernutrition, despite a lack of substantive evidence. In this paper we assess this tenuous evidence base by exploring two key channels by which agricultural production conditions can influence nutritional outomes: a food consumption pathway and a maternal employment–time use pathway. We conclude with an appraisal of some possible entry points for pro-nutrition agricultural policies. 相似文献
24.
Jun Wang Cheuk Tang Mario G. Ferruzzi Bing Gong Brian J. Song Elsa M. Janle Tzu‐Ying Chen Bruce Cooper Merina Varghese Alice Cheng Daniel Freire Amanda Bilski Jessica Roman Tuyen Nguyen Lap Ho Stephen T. Talcott James E. Simon Qingli Wu Giulio M. Pasinetti 《Molecular nutrition & food research》2013,57(12):2091-2102
25.
Fruits are composite materials often surrounded by a skin and sometimes containing rigid stones (pits). To understand the contribution of skin and stone to the overall texture of the fruit, model fruits were constructed from molded gelatin spheres, with rigid inclusions and a skin layer. Cross polarized light revealed the stress distribution during puncture testing and the mechanical measures of firmness, Poisson's ratio and breaking force were determined. Skin significantly raised the breaking force. Spherical stones raised the firmness—effectively reducing the deformable material in the sphere, resulting in inflated strains. Disc shaped stones compared with spherical ones, with the narrow edge normal to the force acted like an internal blade and significantly lowered the breaking force. Neither skin nor stone had any significant impact on Poisson's ratio. Three examples of real fruit (raspberries, grapes, and cherries) were tested to contextualize the findings.
Practical applications
Consumers gently squeeze fruit to gauge ripeness. Unwittingly, what we perceive while squeezing fruit is not wholly dependent on the texture of the internal flesh. In this work, we have attempted to model how the firmness and breaking force are influenced by the presence of a skin and stones of various size and shape. This has implications in both sensory and instrumental fruit testing. 相似文献26.
2023年6月,蒂芙尼(Tiffany&Co.)回溯品牌传奇设计师让·史隆伯杰的妙趣巧思,发布全新“2023 Blue Book高级珠宝”系列之“幻海秘境(Out of the Blue)”,以卓尔不凡的设计致敬这位大师对海洋奇珍的热忱与钟爱。作为蒂芙尼珠宝与高级珠宝首席艺术官娜塔莉·韦代耶(Nathalie Verdeille)加入品牌后设计的首个“Blue Book高级珠宝”系列,新作从让·史隆伯杰非凡的想象与设计哲学中采撷灵感,以几何美学与风格化的艺术笔触,以蓝海绮境致敬传奇设计师让·史隆伯杰,续写品牌奇幻神秘的蔚蓝史诗。 相似文献
27.
Use of cysteine to remove mercury from shark muscle 总被引:1,自引:0,他引:1
Isabel C. M. Aizpur£a Alfredo Tenuta-Filho Alice M. Sakuma & Odair Zenebon 《International Journal of Food Science & Technology》1997,32(4):333-337
The efficiency of cysteine to remove mercury from sliced and minced shark was evaluated. Treatment with 0.5% cysteine at pH 2.0–2.5 and subsequent washing with sodium chloride (5%) failed to remove the mercury from the sliced shark. The efficiency of 0.5% cysteine at pH 7.0 in removing mercury from minced shark was 40–45% (dry material), obtained by two of the three methods studied. This removal rate was considered relatively low for it failed to attend to the practical proposal of decontaminating species of fish highly contaminated by mercury. The need for fuller understanding of the mechanisms involved in the removal of mercury by cysteine was also considered. 相似文献
28.
Templeton AS Trainor TP Spormann AM Newville M Sutton SR Dohnalkova A Gorby Y Brown GE 《Environmental science & technology》2003,37(2):300-307
X-ray spectroscopy measurements have been combined with macroscopic uptake data and transmission electron microscopy (TEM) results to show that Pb(II) uptake by Burkholderia cepacia is due to simultaneous sorption and biomineralization processes. X-ray microprobe mapping of B. cepacia biofilms formed on alpha-Al2O3 surfaces shows that Pb(II) is distributed heterogeneously throughout the biofilms because of the formation of Pb "hot spots". EXAFS data and TEM observations show that the enhanced Pb accumulation is due to the formation of nanoscale crystals of pyromorphite (Pb5(PO4)3(OH)) adjacent to the outer-membrane of a fraction of the total population of B. cepacia cells. In contrast, B. cepacia cell suspensions or biofilms that were heat-killed or pretreated with X-rays do not form pyromorphite, which suggests that metabolic activity is required. Precipitation of pyromorphite occurs over several orders of magnitude in [H-] and [Pb] and accounts for approximately 90% of the total Pb uptake below pH 4.5 but only 45-60% at near-neutral pH because of the formation of additional Pb(II) adsorption complexes. Structural fits of Pb L(III) EXAFS data collected for heat-treated cells at near-neutral pH suggest that Pb(II) forms inner-sphere adsorption complexes with carboxyl functional groups in the biofilms. 相似文献
29.
Estrogen content of dairy and swine wastes 总被引:3,自引:0,他引:3
Raman DR Williams EL Layton AC Burns RT Easter JP Daugherty AS Mullen MD Sayler GS 《Environmental science & technology》2004,38(13):3567-3573
Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentrations in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17beta-estradiol (E2), estrone (E1), and 17alpha-estradiol by gas chromatography-mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to areal mass application rates of estrogen to fields. Swine farrowing waste (from farrowing sows and piglets) had the highest ratios of E2 to macronutrients. Mean ratios in swine farrowing waste were roughly twice those in swine finishing waste (from growing male and nonpregnant female animals) and more than four times higher than those in dairy waste (from lactating cows in various stages of their reproductive cycles); these differences were statistically significant (alpha = 0.05). Estrone followed a similar trend. In contrast, ratios of 17alpha-estradiol to macronutrients were highest in dairy operations. These results can be used to better predict estrogen loading rates on fields receiving swine and dairy wastes. 相似文献
30.
Federico Bolognesi Nicola Fazio Filippo Boriani Viscardo Paolo Fabbri Davide Gravina Francesca Alice Pedrini Nicoletta Zini Michelina Greco Michela Paolucci Maria Carla Re Sofia Asioli Maria Pia Foschini Antonietta DErrico Nicola Baldini Claudio Marchetti 《International journal of molecular sciences》2022,23(3)
Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze–thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique. 相似文献