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Effect of phytase on phosphorous balance in 20-kg barrows fed low or adequate phosphorous diets

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Animal Nutrition 2020年第1期6卷 9-15页

作者： Tsung Cheng Tsai robert Dove Michael R.Bedford Michael j.Azain Animal&Dairy Science Department University of GeorgiaAthensGA 30602United States AB-VISTA Feed Ingredients MarlboroughWiltsMG SN84ANUnited Kingdom Department of Animal Science University of ArkansasFayettevilleAR 72701United States

The effects of phytase on phosphorus(P)digestibility are well ***,there are few studies that report P balance,particularly when phytase is used in diets that have adequate or deficient *** main objective of the study was to determine the effect of dietary P levels and exogenous phytase on P balance in growing *** first part of the experiment was a 14-d metabolism study conducted with 80 barrows(initial body weight 18.5±0.5 kg)with a 2 x 5 factorial arrangement of treatments and main effects of available P(0.13%available P,low P[Low-P]diet;0.35%available P,adequate P[Adeq-P]diet)and phytase(0,250,500,2,500,and 12,500 U/kg).A portion of the pigs(n=24)fed the Low-P diet,with0,500,2,500,12,500 U/kg phytase,and those fed the Adeq-P diet,with 0 and 12,500 U/kg phytase,remained on test diets for another 4 d,and tissues were collected for determination of bone characteristics and tissue P *** was a P×phytase interaction for P retention that was accounted for by a lack of re sponse to phytase in pigs fed the Adeq-P *** of P was greater with incremental levels of phytase in pigs fed Low-P diets as compared to those fed Adeq-P diets(P level x phytase,P<0.01),but calcium(Ca)retention was greater in pigs fed Adeq-P diets(P level x phytase P<0.01).Apparent total tract digestibility(ATTD)of P was improved by phytase(P<0.001)and was greater in pigs fed Adeq-P diets as compared to those fed Low-P diets(P=0.006).Metatarsal bone ash(quadratic,P=0.01)and strength(linear,P=0.03)was increased by phytase addition to the Low-P *** were no phytase or dietary P effects on P concentrations of the heart,kidney,liver,muscle,and *** results suggest that as compared to the effects in an Adeq-P diet,adding phytase to a Low-P diet was more effective at reducing the P and Ca excretion and restoring average daily gain(ADG).The P released by phytase is absorbed and contributes to improved bone growth,greater rates of tissue accretion,a

关键词： Phosphorous Phytase Bone Calcium Digestibility Tissue

Securing Data in Multimode Fibers by Exploiting Mode-Dependent Light Propagation Effects

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Research 2023年第3期2023卷 669-682页

作者： Stefan Rothe Karl-Ludwig Besser David Krause robert Kuschmierz Nektarios Koukourakis Eduard jorswieck jürgen W.Czarske TU Dresden Faculty of Electrical and Computer EngineeringLaboratory of Measurement and Sensor System Technique01062 DresdenGermany TU Braunschweig Faculty of Electrical EngineeringInformation TechnologyPhysicsInstitute for Communications Technology38106 BraunschweigGermany TU Dresden Faculty of Physics01062 DresdenGermany

Multimode fibers hold great promise to advance data rates in optical communications but come with the challenge to compensate for modal crosstalk and mode-dependent losses,resulting in strong *** holographic measurement of the transmission matrix enables not only correcting distortions but also harnessing these effects for creating a confidential data connection between legitimate communication parties,Alice and *** feasibility of this physical-layer-security-based approach is demonstrated experimentally for the first time on a multimode fiber link to which the eavesdropper Eve is physically *** the proper structured light field is launched at Alice’s side,the message can be delivered to Bob,and,simultaneously,the decipherment for an illegitimate wiretapper Eve is *** a real communication scenario,we implement wiretap codes and demonstrate confidentiality by quantifying the level of *** to an uncoded data transmission,the amount of securely exchanged data is enhanced by a factor of *** complex light transportation phenomena that have long been considered limiting and have restricted the widespread use of multimode fiber are exploited for opening new perspectives on information security in spatial multiplexing communication systems.

关键词： distortion destroyed holographic

Adult bobcat(Lynx rufus)habitat selection in a longleaf pine savanna

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Ecological Processes 2018年第1期7卷 206-217页

作者： Andrew R.Little L.Mike Conner Michael j.Chamberlain Nathan P.Nibbelink robert j.Warren Warnell School of Forestry and Natural Resources University of Georgia180 E.Green StAthensGA 30602USA joseph W.jones Ecological Research Center at Ichauway NewtonGeorgia 39870USA

Background:Pine savannas are primarily managed with frequent prescribed fire(≤3 years)to promote diversity of flora and fauna,and to maintain open,park-like conditions needed by species such as the endangered red-cockaded woodpecker(Picoides borealis).However,a knowledge gap exists in our understanding of bobcat(Lynx rufus)habitat selection in longleaf pine savannas and research is warranted to direct our future management ***:We examined bobcat habitat selection in a pine savanna managed with frequent fires at two spatial scales(i.e.,study area boundary[hereafter,landscape scale])and annual area of use[95%kernel density;local scale],and assessed effects of prescribed fire on bobcat habitat ***,we monitored 45 bobcats(16 males and 29 females)during 2001–***:We found differential habitat selection by *** the landscape scale,female bobcats were closer to mixed pine-hardwoods,young pine,and secondary roads,but farther from mature pine and hardwoods stands relative to *** found no difference in selection of agriculture,shrub-scrub,and primary roads between *** the annual area of use scale,female bobcats were closer to secondary roads,but farther from agriculture and shrub-scrub relative to *** found no difference in selection of mature pine,mixed pine-hardwoods,hardwoods,young pine,and primary roads between *** primarily selected for stands burned≤1.1 years ***:Our results show that bobcats exploit a broad range of habitat types in pine landscapes managed with frequent fire and commonly use recently burned stands(≤1.1 year post-fire),suggesting prey in many areas of this system are at risk of bobcat ***,we suggest land managers consider scale of selection by bobcats when developing habitat management strategies.

关键词： Georgia Habitat selection Lynx rufus Pinus palustris Prescribed fire

Eastern gray squirrels are consistent shoppers of seed traits:insights from discrete choice experiments

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Integrative Zoology 2018年第3期13卷 280-296页

作者： Mekala SUNDARAM Nathanael I.LICHTI Nicole j.Olynk WIDMAR robert K.SWIHART Department of Forestry and Natural Resources Purdue UniversityWest LafayetteIndianaUSA Department of Agricultural Economics Purdue UniversityWest LafayetteIndianaUSA

Seeds of many hardwood trees are dispersed by scatter-hoarding rodents,and this process is often mediated by the traits of *** numerous studies have linked seed traits to seed preference by rodents,little is known about how rodents forage for seeds when multiple desirable and undesirable seed traits are available ***,we adopt a novel method of designing choice experiments to study how eastern gray squirrels(Sciurus carolinensis)select for 6 traits(caloric value,protein content,tannin concentration,kernel mass,dormancy period and toughness of shell)among *** n=426 seed-pair presentations,we found that squirrels preferentially consumed seeds with short dormancy or tougher shells,and preferentially cached seeds with larger kernel mass,tougher shells and higher tannin *** incorporating random effects,we found that squirrels exhibited consistent preferences for seed traits,which is likely due to the fitness consequences associated with maintaining cached ***,we found that squirrels were willing to trade between multiple traits when caching seeds,which likely results in more seed species being cached in the ***,our approach allowed us to compute the relative values of different seed traits to squirrels,despite covariance among studied traits across seed *** addition,by investigating how squirrels trade among different seed traits,important insights can be gleaned into behavioral mechanisms underlying seed caching(and,thus,seed survival)dynamics as well as evolutionary strategies adopted by plants to attract seed *** describe how discrete choice experiments can be used to study resource selection in other ecological systems.

关键词： cached resources discrete choice experiment resource selection trade-offs trait-dependent

Identifying candidate hosts for quantum defects via data mining

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npj Computational Materials 2020年第1期6卷 595-600页

作者： Austin M.Ferrenti Nathalie Pde Leon jeff D.Thompson robert j.Cava Department of Chemistry Princeton UniversityPrincetonNJ 08544USA Department of Electrical Engineering Princeton UniversityPrincetonNJ 08544USA

Atom-like defects in solid-state hosts are promising candidates for the development of quantum information systems,but despite their importance,the host substrate/defect combinations currently under study have almost exclusively been found *** we systematically evaluate the suitability of host materials by applying a combined four-stage data mining and manual screening process to all entries in the Materials Project database,with literature-based experimental confirmation of band gap values.

关键词： quantum applying suitability

Context-free Grammars for Triangular Arrays

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Acta Mathematica Sinica,English Series 2015年第3期31卷 445-455页

作者： robert X.j.HAO Larry X.W.WANG Harold R.L.YANG Center for Combinatorics LPMC-TJKLC Nankai University

We consider context-free grammars of the form G = {f → f^b1＋b2＋1g^a1＋a2, g → f^b1 g^a1＋1},where ai and bi are integers sub ject to certain positivity conditions. Such a grammar G gives rise to triangular arrays {T（n, k）}0≤k≤n satisfying a three-term recurrence relation. Many combinatorial sequences can be generated in this way. Let Tn （x） =∑k=0^n T（n, k）x^k. Based on the differential operator with respect to G, we define a sequence of linear operators Pn such that Tn＋1（x） = Pn（Tn（x））. Applying the characterization of real stability preserving linear operators on the multivariate polynomials due to Borcea and Br？ndén, we obtain a necessary and sufficient condition for the operator Pn to be real stability preserving for any n. As a consequence, we are led to a sufficient condition for the real-rootedness of the polynomials defined by certain triangular arrays, obtained by Wang and ***, as special cases we obtain grammars that lead to identities involving the Whitney numbers and the Bessel numbers.

关键词： Context-free grammar stable polynomials real-rootedness Bessel numbers Whitneynumbers

Applying reticular synthesis to the design of Cu-based MOFs with mechanically interlocked linkers

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Nano Research 2021年第2期14卷 417-422页

作者： Alexander j.Stirk Benjamin H.Wilson Christopher A.O’Keefe Hazem Amame Kelong Zhu robert W.Schurko Stephen j.Loeb Department of Chemistry and Biochemistry University of WindsorWindsorOntarioN9B 3B4Canada Department of Chemistry The University of JordanAmman11942Jordan School of Chemistry Sun Yat-Sen UniversityGuangzhou 510275China Department of Chemistry and Biochemistry Florida State UniversityTallahasseeFlorida 32306-4390USA

The concept of“robust dynamics”describes the incorporation of mechanically interlocked molecules(MIMs)into metal-organic framework(MOF)materials such that large amplitude motions(e.g.,rotation or translation of a macrocycle)can occur inside the free volume pore of the *** aid in the preparation of such materials,reticular synthesis was used herein to design rigid molecular building blocks with predetermined ordered structures starting from the well-known MOF *** linkers were synthesized that have a T-shape,based on a triphenylene tetra-carboxylate strut,and their incorporation into Cu(II)-based MOFs was *** single-crystal structures of three new MOFs,UWCM-12(fof),β-UWCM-13(loz),UWCM-14(lil),with naked T-shaped linkers were determined;β-UWCM-13 is the first reported example of the loz topology.A fourth MOF,UWDM-14(lil)is analogous to UWCM-14(lil)but contains a[2]rotaxane ***-temperature,^(2)H solid-state NMR was used to probe the dynamics of a 24-membered macrocycle threaded onto the MOF skeleton.

关键词： reticular chemistry metal-organic frameworks mechanically interlocked molecules rotaxane

Oxidative stress and male reproductive health

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Asian journal of Andrology 2014年第1期16卷 31-38页

作者： robert j Aitken Tegan B Smith Matthew S jobling Mark A Baker Geoffry N De Iuliis Priority Research Centre in Reproductive Science Discipline of Biological Sciences Faculty of Science and IT University of Newcastle Callaghan NSW 2308 Australia

One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high leve｜s of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair （BER） pathway, 8-oxoguanine glycosylase 1 （OGG1）. The latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins （APE1, XRCC1） needed to complete the repair process. It is the responsibility of the oocyte to continue the BER pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. Such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

关键词： DNA damage oxidative stress oxoguanine glycosylase 1 oocyte spermatozoa

DeepRice: A deep learning and deep feature based classification of Rice leaf disease subtypes

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Artificial Intelligence in Agriculture 2024年第1期11卷 34-49页

作者： P.Isaac Ritharson Kumudha Raimond X.Anitha Mary jennifer Eunice robert Andrew j Department of CSE Karunya Institute of Technology and Sciences CoimbatoreTamilnaduIndia Department of Robotics Engineering Karunya Institute of Technology and SciencesCoimbatoreIndia Department of Mechatronics Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnataka 576104India Department of Computer Science and Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnataka 576104India

Rice stands as a crucial staple food globally,with its enduring sustainability hinging on the prompt detection of rice leaf ***,efficiently detecting diseases when they have already occurred holds paramount importance for solving the cost of manual visual identification and chemical *** the recent past,the identification of leaf pathologies in crops predominantly relies on manual methods using specialized equipment,which proves to be time-consuming and *** study offers a remedy by harnessing Deep Learning(DL)and transfer learning techniques to accurately identify and classify rice leaf diseases.A comprehensive dataset comprising 5932 self-generated images of rice leaves was assembled along with the benchmark datasets,categorized into 9 classes irrespective of the extent of disease spread across the *** classes encompass diverse states including healthy leaves,mild and severe blight,mild and severe tungro,mild and severe blast,as well as mild and severe brown *** meticulous manual labelling and dataset segmentation,which was validated by horticulture experts,data augmentation strategies were implemented to amplify the number of *** datasets were subjected to evaluation using the proposed tailored Convolutional Neural Networks *** performance are scrutinized in conjunction with alternative transfer learning approaches like VGG16,Xception,ResNet50,DenseNet121,Inception ResnetV2,and Inception *** effectiveness of the proposed custom VGG16 model was gauged by its capacity to generalize to unseen images,yielding an exceptional accuracy of 99.94%,surpassing the benchmarks set by existing state-of-the-art ***,the layer wise feature extraction is also visualized as the interpretable AI.

关键词： Rice leaf disease Deep learning CNN Crop yield Agriculture Food security