bluuebunny/crossref_metadata_2025_split huggingface dataset:
Free and Forced Vibration Methods in the Measurement of the Dynamic Properties of Rubbers
Authors: Moyal J. E. , Fletcher W. P. 
Published: February 2011

Abstract
Previous work on the shear elastic modulus and damping factor of rubber has been carried out chiefly by two methods. Some workers have deduced these quantities from the natural frequency and rate of decay of the free vibrations of a simple system comprising a mass and a rubber spring; others have obtained the values from the resonance curve of such a system under forced vibration excited by a known harmonic force of variable frequency. The derivation of the shear modulus and damping factor from the experimental results is in both cases based on the assumption for rubber of a simple mechanical model consisting of a spring with a viscous dashpot in parallel. In order to ascertain whether the results from the two methods (more particularly for the damping factor) correspond, measurements have been carried out by both methods on the same rubber test piece on the same mechanical system and under identical conditions. The approximate agreement between the results thus obtained justifies the basic assumptions underlying these methods.
Physical Examination of Brass Deposits
Authors: Buchan S. , Rae W. D. 
Published: February 2011

Abstract
Microscopic examination of average brass deposits revealed a fairly uniform deposit of thickness varying from 0.0006 to 0.00004 inch, the brass deposit being thinner at the centre of the plate than at the edges. β-brass was obtained at points where porosity occurred in the base metal. The deposit was collected in aggregates or hillocks dispersed fairly evenly over the plate, a condition which was confirmed by examination under the electron microscope. With this instrument it was demonstrated that bad bonding brass was nonuniform over the surface, a fact further substantiated by subsequent x-ray analysis. Differences in crystallite size and in degree of crystalline orientation appeared to have no consistent effect on the bonding properties of the brass. The brass deposit showed, however, a high degree of preferred orientation, as is usual with electrodeposits. As regards the preparation of the base metal, the use of too much oil and too high a speed of machining appeared to have a detrimental effect. This appeared to be due to the fact that a nonuniform state of strain was produced over the surface as samples of mild steel of various degrees of strain, but uniform over the surface, gave consistently good adhesion.
The Infrared Spectra of Compounds of High Molecular Weight
Authors: Thompson H. W. , Torkington P. 
Published: February 2011

Abstract
Many methods are being used at present to explore the reasons for the differences in physical behavior of various types of polymers, plastics, rubbers and other compounds of high molecular weight. The peculiar rheological and electrical properties of many of these substances must be connected with the internal molecular structure and with the way in which the molecules can pack together in the solid and liquid states. Valuable information has already been obtained using the diffraction of x-rays, and some chemical methods have also given useful indications of the nature of the polymerization processes. The determination of molecular weights and chain lengths of fiberlike polymers has also led to important correlations. No method, however, has provided all the information which might enable us to formulate rules correlating properties with structure. It is clear that any method which can examine the sample without the use of chemical reagents is of advantage, and from this standpoint spectroscopy should be useful. The infrared absorption spectra of substances of this type consist essentially of bands which correspond to the absorption of characteristic vibration frequencies of the whole molecule, or of particular units within it. Since, theoretically, no two molecules having a different nuclear skeleton have the same set of vibrational frequencies, we may expect small differences between the spectra of closely related molecules, and a careful analysis of the vibrational spectra may reveal the occurrence of special groups, or the arrangement of the nuclear skeleton within these molecules. For this analysis reference data from the spectra of simple related molecules may first be required. Apart from giving such fundamental structural information, however, the infrared spectra can be used empirically for many practical purposes. Small differences in the properties of samples of the same polymer can sometimes be correlated empirically with small differences in their spectra. The effect of different plasticizing or vulcanizing agents, leading for instance to cross-linking, can also be explored by spectral changes. On the fundamental side too, it is valuable from the standpoint of molecular dynamics to assemble data on long-chain polymeric substances as a basis for the calculation of the vibration frequencies of these molecules as systems of weighted chains. If the molecular dynamics could be understood more completely, it might prove a useful adjunct to the consideration of thermodynamic properties.
Gas Permeability and the Microstructure of Polymers
Authors: Reitlinger S. A. 
Published: February 2011

Abstract
1. The permeability to gas of high molecular-weight polymers is closely connected with the character of the interaction between separate links of adjacent macromolecules, which is governed by the form of the chain and the energy of the intermolecular bonds. 2. The magnitude of permeability increases with increases in the curvature of the principal-valence chains and in the dimensions of the side groups, decreases with increase in the energy of the intermolecular bonds, and is independent of the length of the main valence chains. 3. A comparison of the values of the activation energies and gas permeabilities of a series of polymers makes reasonable the assumption that the principal paths for the penetration of hydrogen molecules lie along the interface between the nonpolar groups of the macromolecular chains.
Mechanism of Rubber Cracking
Authors: Powell E. F. , Gough V. E. 
Published: February 2011

Abstract
Rubber and rubberlike polymers, in common with other materials which deteriorate on exposure to oxidizing or similar agents, eventually crack under normal atmospheric service conditions. The present paper confines itself to the factors affecting the type and appearance of the cracking which eventually occurs when a surface film of a rubber object (particularly when stressed) hardens and deteriorates in strength from any cause whatsoever. The importance of an understanding of the effects of exposure conditions on the character of the cracking produced cannot be too highly emphasized. This is so even if interest is confined solely to simple tests on new protective paints on an acceptance basis rather than research into surface deterioration. It is probable that many protective agencies have been accepted or rejected for extensive production tests because the initial laboratory tests have either not been representative of service or have been inadequate in scope. This still remains a major problem. The theory presented here has gradually taken shape over a period of some ten years and appears to describe adequately the general findings on the whole gamut of cracking, viz., fine check cracking and isolated deep cracks produced under service and laboratory conditions, the latter covering flexing, roof exposure, ozone and similar tests.
Relations between the Quality of Latex and Its Chemical Composition
Authors: Martin George 
Published: February 2011

Abstract
One of the chief technical difficulties when latex is used industrially for the manufacture of rubber articles is that there is no method available for determining whether or not successive shipments of latex are suitable for any particular process of manufacture. Two samples of latex may be similar in appearance and have nearly the same chemical properties with respect to dry rubber content, total solids and alkalinity, yet one sample may be in excellent condition, whereas the other sample is on the point of coagulating. When these two samples are mixed with compounding ingredients, one remains quite fluid, while the other thickens or even coagulates. Then again, when treated with a coagulant, one sample gels in a normal way and under conditions compatible with good processing, whereas the other sample gels either too rapidly or too slowly, or coagulates to an unusable mass. It is safe to say that there is no generally acceptable method with which it is possible to judge the quality of latex, and the different procedures which have been suggested cannot be regarded as satisfactory. Rubber planters have called attention many times to the large variations in the properties of natural latex. Preserved latex is perhaps even more variable, for new factors then enter and influence its properties, e.g., the effects of bacteria before any preservatives are added to the latex, and chemical reactions which take place between certain components of the latex and the preservatives. In addition, the properties of latex change continuously with age, which is extremely limited compared with that of dry rubber.
The Fibrous Properties and Abrasion Resistance of Synthetic Rubber Compounds
Authors: Kusov A. 
Published: February 2011

Abstract
1. A method of measuring the tear resistance of rubber compounds was developed. This method has a number of advantages over other methods (Goodrich, Heidensohn, Goodyear, etc.), including the following. (a) The symmetrical shape and the large surface of tearing (20 sq. cm.). This excludes the possibility of short, accidental tears, and enables better observation of the nature of the tear. (b) Owing to the small size of the clamped portion of the specimen compared to the size of the tearing surface, “end effects” are largely eliminated. (c) Tearing forces are registered periodically (every 10 seconds), and it is possible in this way to determine the total energy expended on tearing, and the nature of its changes. (d) The experiments are easy to perform, and the apparatus is simple. 2. The addition of carbon black (10–100 per cent) to synthetic rubber compounds increases considerably the tear resistances of the vulcanized products. The best results are obtained with compounds containing between 50 and 75 per cent of carbon black. 3. A zinc oxide content of between 8 and 14 per cent improves the tear resistances of compounds of both synthetic and natural rubbers. 4. Compounds with increased fibrous structure show increased abrasion resistance when the fiber direction is parallel to the movement of the abrading surface. 5. Compounds cured for short times only show low tear resistances when made of synthetic rubbers of both low (0.31) and high (0.87) plasticity. The best results are obtained with compounds made of synthetic rubber of medium plasticity (0.53 and 0.40) (see Figure 4). 6. When comparing tear resistances, it is of the utmost importance to maintain the thickness of test-specimens within narrow limits. It is desirable to keep variations within 10–15 per cent. 7. The weakening of the uncut portion of a test-specimen with increase in depth of cut is less pronounced with compounds of synthetic rubber than it is with natural rubber compounds, particularly in the case of overcured samples. With synthetic compounds, this weakening effect varies 2–3 times; with natural rubber compounds it is 3.5–6.5 times. The relation between tear resistance and depth of cut is shown in Figure 5 and Table VI. 8. Carbon black compounds of both synthetic and natural rubbers exhibit various structural forms of tearing. Synthetic rubber compounds with low tear resistances show simple and smooth tearing surfaces, usually in the prolongation of the cut, or at a slight angle to it (Figure 1, type A or intermediate between A and B). Synthetic compounds with high tear resistances show complicated tearing surfaces (Figures 6 and 7, types C, D, E and F).
Metal‐Free One‐Pot Oxidative Amination of Aromatic Aldehydes: Conversion of Benzaldehyde to

N

‐Benzoyl Pyrrolidine
Authors: Ekoue‐Kovi Kekeli , Wolf Christian 
Published: February 2011

Abstract

Benzaldehyde

Pyrrolidine

N
‐Benzoyl pyrrolidine

tert
‐Butyl hydroperoxide
A Practical and Scalable Synthesis of
N
‐Halo Compounds: 2‐Chloro‐6,7‐Dimethoxy‐1,2,3,4‐Tetrahydroisoquinoline
Authors: Zhong Yong‐Li , Bulger Paul G. 
Published: February 2011

Abstract

2‐Chloro‐6,7‐dimethoxy‐1,2,3,4‐tetrahydroisoquinoline

6,7‐Dimethoxy‐1,2,3,4‐tetrahydroisoquinoline hydrochloride

Sodium hypochlorite

tert
‐Butanol
Stereoselective Synthesis of 3‐Arylacrylates by Copper‐Catalyzed Syn Hydroarylation
Authors: Kirai Naohiro , Yamamoto Yoshihiko 
Published: February 2011

Abstract

2‐Octynoic acid, methyl ester

Boronic acid, phenyl

Acetic acid, copper (1+) salt

2‐Octenoic acid, 3‐phenyl‐, methyl ester
Preparation of (

S

)‐3,3'‐Bis‐morpholinomethyl‐5,5',6,6',7,7',8,8'‐octahydro‐1,1'‐bi‐2‐naphthol
Authors: Turlington Mark , Pu Lin 
Published: February 2011

Abstract

Paraformaldehyde

Morpholine

Morpholinomethanol

(
S
)‐5,5′,6,6′,7,7′,8,8′‐Octahydro‐1,1′bi‐2‐napthol [(
S
)‐H
8
BIBOL]

(S
)‐3,3′‐Bismorpholinomethyl 5,5′,6,6′,7,7′,8,8′‐octahydro‐1,1′‐bi‐2‐naphthol
Catalytic Asymmetric Addition of an

in

‐

situ

Prepared Arylzinc to Cyclohexanecarboxaldehyde: (

R

)‐(+)‐α‐cyclohexyl‐3‐methoxy‐benzenemethanol
Authors: DeBerardinis Albert M. , Turlington Mark , Pu Lin 
Published: February 2011

Abstract

Lithium acetylacetonate

3‐Iodoanisole

Diethyl zinc

(
S
)‐3,3'‐Bis‐morpholinomethyl‐5,5',6,6',7,7'8,8'‐octahydro1‐1'‐bi‐2‐naphthol

Cyclohexanecarboxaldehdye

(R)‐(+)‐alpha‐Cyclohexyl‐3‐methoxy‐benzenemethanol
Microwave‐Assisted Synthesis of 1,3‐Dimesitylimidazolinium Chloride
Authors: Hans Morgan , Delaude Lionel 
Published: February 2011

AbstractLithium acetylacetonate3‐IodoanisoleDiethyl zinc(S)‐3,3'‐Bis‐morpholinomethyl‐5,5',6,6',7,7'8,8'‐octahydro1‐1'‐bi‐2‐naphtholCyclohexanecarboxaldehdye(R)‐(+)‐alpha‐Cyclohexyl‐3‐methoxy‐benzenemethanol
Palladium‐Catalyzed Cross‐Coupling Using an Air‐Stable Trimethylaluminum Source. Preparation of Ethyl 4‐Methylbenzoate
Authors: Vinogradov Andrej , Woodward Simon 
Published: February 2011

Abstract

Trimethylaluminum

DABCO

Pd2(dba)3

X‐Phos

Ethyl 4‐bromobenzoate
Synthesis of Dimethyl 2‐Phenylcyclopropane‐1,1‐Dicarboxylate Using an Iodonium Ylide Derived from Dimethyl Malonate
Authors: Goudreau Sébastien R. , Marcoux David , Charette André B. 
Published: February 2011

Abstract

Potassium hydroxide

Dimethyl malonate

Iodosobenzene diacetate

Bis[rhodium(a,a,a′a′‐tetramethyl‐1,3‐benznedipropionic acid)]

Styrene

Thiourea
Preparation of Ethyl 1‐Benzyl‐4‐Fluoropiperidine‐4‐Carboxylate
Authors: Kong Jianshe , Meng Tao , Ting Pauline , Wong Jesse 
Published: February 2011

Abstract

Disiopropylamine

n
‐Butyllithium

Ethyl isonipectoate

Benzyl bromide

Ethyl 1‐benzylpiperidine‐4‐carboxylate

N
‐Fluorobenzenesulfonimide
Synthesis of Tetraorganosilanes: (Chloromethyl)Dimethylphenylsilane
Authors: Murakami Kei , Yorimitsu Hideki , Oshima Koichiro 
Published: February 2011

Abstract

Bromobenzene

Magnesium

Dichloro(
N,N,N′N′
‐tetramethylethylenediamine)zinc

Chloro(chloromethyl)dimethylsilane

(Chloromethyl)dimethylphenylsilane
One‐Pot Diazotization and Heck Reaction of Methyl Anthranilate: 2‐(3‐Oxopropyl)Benzoic Acid Methyl Ester
Authors: Zaragoza Florencio 
Published: February 2011

Abstract

Methyl anthranilate

Allyl alcohol

Methyl‐2‐(3‐oxopropyl)enzoate
Synthesis of Ynamides by Copper‐Mediated Coupling of 1,1‐Dibromo‐1‐Alkenes with Nitrogen Nucleophiles. Preparation of 4‐Methyl‐

N

‐(2‐Phenylethynyl)‐

N

‐(Phenylmethyl)Benzenesulfonamide
Authors: Coste Alexis , Couty François , Evano Gwilherm 
Published: February 2011

Abstract

4‐Methyl‐
N
‐(phenylmethyl)benzenesulfonamide

P
‐Toluenesulfonyl chloride

Triethylamine

(2,2‐Dibromoethenyl0benzene

Carbon tetrabromide

Triisopropyl phosphite

Benzaldehyde

4‐Methyl‐
N‐(
2‐phenylethynyl)‐
N
‐(phenylmethyl)benzenesulfonamide

Cesium carbonate

N,N‐
Dimethylethylenediamine
Preparation and [2+2] Cycloaddition of 1‐Triisopropylsiloxy‐1‐Hexyne with Methyl Crotonate: 3‐Butyl‐4‐Methyl‐2‐Triisopropylsiloxy‐Cyclobut‐2‐Enecarboxylic Acid Methyl Ester
Authors: Shubinets Valeriy , Schramm Michael P. , Kozmin Sergey A. 
Published: February 2011

Abstract

Methyl crotonate

Triisopropylsilyl trifluoromethanesulfonate

Trifluoromethanesulfonanimide

Silver carbonate
Synthesis of Enamides from Ketones: Preparation of

N

‐(3,4‐Dihydronaphthalene‐1‐Yl)Acetamide
Authors: Zhao Hang , Vandenbossche Charles P. , Koenig Stefan G. , Singh Surendra P. , Bakale Roger P. 
Published: February 2011

Abstract

3,4‐Dihydronaphthalene‐1(2
H
)‐one oxime

Hydroxylamine hydrochloride

a‐Tetralone

N
‐(3,4)dihydronaphthalene‐1‐yl)acetamide

Triethylphosphine

Acetic anhydride
Palladium‐Catalyzed Alkyl‐Alkyl Suzuki Cross‐Couplings of Primary Alkyl Bromides at Room Temperature: (13‐Chlorotridecyloxy)Triethylsilane
Authors: Lou Sha , Fu Gregory C. 
Published: February 2011

Abstract8‐Bromo‐1‐octanolDichlorotriphenylphosphoraneImidazole4‐Penten‐1‐olChlorotriethylsilaneTriethyl(pent‐4‐enoxy)silane9‐BBNPalladium(II) acetateBicyclohexylphosphineTripotassium phosphate monohydrate(13‐Chlorotridecyloxy)trietylsilane
Synthesis of Chiral Pyridine Bis(Oxazoline) Ligands for Nickel‐Catalyzed Asymmetric Negishi Cross‐Couplings of Secondary Allylic Chlorides with Alkylzincs: 2,6‐Bis[(4

R

)‐4,5‐Dihydro‐4‐ (2‐Phenylethyl)‐2‐Oxazolyl]‐ Pyridine
Authors: Lou Sha , Fu Gregory C. 
Published: February 2011

Abstract

L‐Homophenylalanine

D‐Homophenylalanine, ethyl ester hydrochloride

Lithium aluminum hydride

(
S
)‐2‐Amino‐4‐phenylbutan‐1‐ol

(
R
)‐2‐Amino‐4‐phenylbutan‐1‐ol

2,6‐Pyridinedicarbonitrile

Zinc trifluormethanesulfonate

2,6‐Bis[4
R
)‐4,5 dihydro‐4(2‐phenylethyl)2‐oxazolyl]pyridine
Nickel‐Catalyzed Asymmetric Negishi Cross‐Couplings of Racemic Secondary Allylic Chlorides with Alkylzincs: (

S

,

E

)‐Ethyl 6‐(1,3‐Dioxolan‐2‐Yl)‐4‐Methylhex‐2‐Enoate
Authors: Lou Sha , Fu Gregory C. 
Published: February 2011

Abstract

Ethyl(
E
)‐4‐oxo‐2‐butenoate

Methylmagnesium

Ethyl (
E
)‐4‐hydroxy‐2‐pentanoate

Dichlorotriphenylphosporate

Ethyl (
E
)‐4‐chloro‐2‐enaote

2‐(1,3‐Dioxolan‐2‐yl)ethyl bromide

2‐[2‐(1,3‐Dioxolan‐2‐yl)ethyl]zinc

Nickel(II) chloride, dimethoxyethane adduct

2,6‐Bis(S)‐4,5‐dihydro‐4‐(2‐phenylethyl)2‐oxazoyl]pyridine

(S,E)‐Ethyl‐6‐(1,3‐dioxolan‐2‐yl)‐4‐methyllhex‐2‐enolate
One‐Pot Synthesis of 5

H

‐Indazolo‐[3,2‐

B

]benzo[

d

]‐1,3‐Oxazine: Two Efficient Preparative Methods
Authors: Solano Danielle M. , Butler Jeffrey D. , Haddadin Makhluf J. , Kurth Mark J. 
Published: February 2011

Abstract

2‐Nitrobenzaldehyde

2‐Aminobenzyl alcohol

2‐Picoline borane

5
H‐
Indazolo‐[3,2b]benzo[d]‐1,3‐oxazine

2‐Nitrobenzyl bromide

Diisopropylethyl amine
Preparation of Chiral and Achiral Triazolium Salts: Carbene Precursors with Demonstrated Synthetic Utility
Authors: Vora Harit U. , Lathrop Stephen P. , Reynolds Nathan T. , Kerr Mark S. , de Alaniz Javier Read , Rovis Tomislav 
Published: February 2011

Abstract

4,4a,9,9a‐Tetrahydro‐1‐oxa‐4‐azafluoren‐3‐one

(1
R
, 2
S
)‐(+)‐
cis
‐!‐Amino‐indol

2‐Pentafluorophenyl‐6,10b‐dihydro‐4
H
,5a
H
‐5‐oxa‐3,10c‐diaza‐2azoniacyclopenta[
c
]fluorene;tetraborate

Trimethyloxonium tetrafluoroborate

Pentafluorophenyhydrazine
Development of Chemical Probes for Biochemical Detection and Cellular Imaging of Myristoylated and Palmitoylated Proteins
Authors: Hannoush Rami N. 
Published: February 2011

AbstractFatty acylation of proteins regulates their spatial localization and activity in living cells. Methods to monitor fatty acylation are invaluable for studying its role in regulating protein dynamics. The protocols in this unit describe a procedure that involves metabolic labeling with ω‐alkynyl fatty acids for detecting and cellular imaging of fatty‐acylated proteins, namely myristoylated and palmitoylated proteins. Curr. Protoc. Chem. Biol. 3:15‐26 © 2011 by John Wiley & Sons, Inc.
Multiplexed Detection with Magnetic Nanoparticles
Authors: Wilson Robert 
Published: February 2011

AbstractThe sections in this article areIntroductionMagnetism and Magnetic ParticlesSeparating and Mixing Magnetic ParticlesPlanar ArraysRotating DiscsDiagnostic DevicesBio‐Barcode Assays Based on Magnetic MicrospheresSpectrally Encoded Suspension Arrays of Magnetic MicrospheresMagnetically Encoded Suspension ArraysSummary and Conclusions
Magnetic Nanoparticles for Cancer Imaging and Therapy
Authors: Natarajan Arutselvan , Sundrarajan Rajeswari , DeNardo Sally J. 
Published: February 2011

AbstractThe sections in this article areIntroductionSynthesis and Surface Modifications ofMNPsfor Biological ApplicationsFabrication of the Magnetic Nanoparticle CoreSurface Coatings and ChemistryPhysico‐Chemical Characterization ofMNPsPlasma Stability and Pharmacokinetic Profile of theMNPsDevelopment ofMNPsas Cancer Diagnosis and Imaging AgentsMNPsUsed inMRImaging for Cancer DiagnosisMNPsUsed in Optical Imaging for Cancer DiagnosisLigand‐DirectedMNPsfor Cancer ImagingAntibody‐DirectedMNPsAntibody Fragment‐DirectedMNPsRadioimmunonanoparticlesAnnexin 5‐DirectedMNPsChemotherapeutic Drugs Loaded withMNPsfor Cancer TherapyLymph Node‐TargetingMNPsOther NovelMNPsfor Cancer TargetingMNPsApplied to Cancer TherapyMNPsUtilized in Targeted Therapy for CancerBrain Tumor TherapyBreast Cancer TherapyMNPsin Hyperthermia and Thermal AblationMNPs‐Directed ToxicitySummary
Core–Shell Magnetic Nanomaterials in Medical Diagnosis and Therapy
Authors: Melancon Marites P. , Li Chun 
Published: February 2011

AbstractThe sections in this article areIntroductionSynthesisFormation of the Magnetic CoreCoprecipitation from SolutionThermal DecompositionMicroemulsionsPyrolysisFormation of the Core–Shell StructureInorganic Core with Organic ShellInorganic Core with Inorganic ShellApplications: Magnetic Resonance ImagingApplications: Hyperthermia and Thermal AblationPassive TargetingDextran‐Coated MagnetiteAminosilan‐Coated Magnetic ParticlesMagnetic Cationic LiposomesActive TargetingAntibodiesPeptidesFolic AcidLaser‐Induced Hyperthermia/Thermal Ablation TherapyApplication: Drug DeliverySummary and PerspectivesAcknowledgments
Magnetic Nanomaterials for Environmental Applications
Authors: Warner Marvin G. , Warner Cynthia L. , Addleman R. Shane , Yantasee Wassana 
Published: February 2011

AbstractThe sections in this article areIntroductionThe Aim of the ChapterThe Role of Nanomaterials in Environmental DetectionSynthesis and Functionalization of Magnetic NanoparticlesSynthetic Strategies for Magnetic Metal Oxide NanoparticlesCoprecipitationThermal DecompositionOther Synthetic MethodsFunctionalization of Magnetic NanoparticlesOrganic Ligand ModificationStabilization with PolymersInorganic Stabilization with Silica or CarbonLess Common Methods of PassivationMagnetic Nanoparticles for the Separation and Detection of AnalytesChemical Separations with Functionalized Magnetic NanoparticlesHigh Magnetic Field Gradient Separation and PreconcentrationElectrochemical Detection Enhanced by Magnetic Nanomaterials for PreconcentrationAnalyte Detection Using Magnetic Nanoparticles through Nonelectrochemical MethodsSummary and Future PerspectiveAcknowledgments