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Returns to Lying？ Identifying the Effects of MisreporUng When the Truth Is Unobserved

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2012年第2期7卷 163-192页

作者： Yingyao Hu arthur Lewbel department of Economics Johns Hopkins University Baltimore MD 21218 USA department of Economics Boston College Boston MA 02467 USA

Consider an observed binary regressor d and an unobserved binary vari- able d＊, both of which affect some other variable Y. This paper considers nonpara- metric identification and estimation of the effect of d on Y, conditioning on d＊ = 0. For example, suppose Y is a person＇s wage, the unobserved d＊ indicates if the person has been to college, and the observed d indicates whether the individual claims to have been to college. This paper then identifies and estimates the difference in av- erage wages between those who falsely claim college experience versus those who tell the truth about not having college. We estimate this average effect of lying to be about 6% to 20%. Nonparametric identification without observing d＊ is obtained ei- ther by observing a variable V that is roughly analogous to an instrument for ordinary measurement error, or by imposing restrictions on model error moments.

关键词： binary regressor misclassification measurement error unobserved factor discrete factor program evaluation treatment effects returns to schooling wage model

Pseudo-depth/Intercept-Time Monotonicity Requirements in the Inverse Scattering Algorithm for Predicting Internal Multiple Reflections

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Communications in Computational Physics 2009年第1期5卷 163-182页

作者： Bogdan G.Nita arthur B.Weglein department of Mathematical Sciences Montclair State University1 Normal AvenueMontclairNJ 07043USA. department of Physics University of Houston617 Science and Research Bldg.1HoustonTX 77004USA

In this paper we discuss the inverse scattering algorithm for predicting internal multiple reflections(reverberation artefacts),focusing our attention on the construction *** speaking,the algorithm combines amplitude and phase information of three different arrivals(sub-events)in the data set to predict one multiple *** three events are conditioned by a certain relation which requires that their pseudo-depths,defined as the depths of their turning points relative to the constant background velocity,satisfy a lower-higher-lower *** implicitly assumes a pseudo-depth monotonicity condition,i.e.,the relation between the actual depths and the pseudo-depths of any two sub-events is the *** study this relation in pseudo-depth and show that it is directly connected with a similar relation between the vertical or intercept times of the *** paper also provides the first multidimensional analysis of the algorithm(for a vertically varying acoustic model)with analytical *** show that the construction of internal multiples is performed in the plane waves domain and,as a consequence,the internal multiples with headwaves sub-events are also predicted by the *** we analyze the differences between the time monotonicity condition in vertical or intercept time and total travel time and show a 2d example which satisfies the former but not the *** we discuss one case in which the monotonicity condition is not satisfied by the sub-events of an internal multiple and discuss ways of lowering these restrictions and of expanding the algorithm to address these types of multiples.

关键词： Multiple reflections seismic imaging inverse scattering

Modified malleable prosthesis with a fixed mesh:case series for the Ghattas technique

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Asian Journal of Andrology 2022年第2期24卷 167-170页

作者： Osama Ghattas Mohamed Fahmy doheim Hossam Kotb arthur L Burnett dar-elzokora Center of Andrology Alexandria 21500Egypt Alexandria Faculty of Medicine Alexandria UniversityAlexandria 21131Egypt department of Urology Johns Hopkins University School of MedicineBaltimoreMD 21287USA

Penile prosthetic implantation represents a cornerstone for patients with organic erectile dysfunction(Ed)that is refractory,unsatisfactory,or contra-indicated for other approved medical or mechanical *** this study,we introduce the“Ghattas technique,”wherein we constructed a polypropylene mesh sheath that surrounds and is fixed to a 13-mm malleable prosthesis cylinder,which can increase the cylinder diameter for cases that need a larger *** patients underwent preoperative evaluation and completed the five-item International Index of Erectile Function questionnaire(IIEF-5).Postoperative outcomes were evaluated by IIEF-5 and Erectile dysfunction Inventory of Treatment Satisfaction(EdITS)questionnaires at final *** mean age of the 23 included patients was 57.9(standard deviation[s.d.]:11.4)years and the mean duration of Ed was 8.5(s.d.:7.9)*** improvement was determined by comparing mean preoperative and postoperative IIEF-5 scores(8.3[s.d.:3.9]vs 24.6[s.d.:0.6],Pdetermined according to a mean EdITS score of 94.9(s.d.:9.9).The proposed Ghattas technique was safe and effective in our patients,and provides opportunity for cases that need a diameter larger than 13 *** studies are needed to confirm these results.

关键词： erectile dysfunction mesh penile prosthesis surgical technique

Speed kills: Highly relativistic spaceflight would be fatal for passengers and instruments

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Natural Science 2012年第10期4卷 749-754页

作者： William A. Edelstein arthur d. Edelstein Johns Hopkins School of Medicine Baltimore USA University of California San Francisco San Francisco USA

Highly relativistic speeds are desirable for interstellar travel. Relativistic time dilation would reduce the subjective duration of the trip for the travelers, so that they can cover galaxy-scale distances in a reasonable amount of personal time. Unfortunately, as spaceship velocities approach the speed of light, interstellar hydrogen H, although only present at a density of approximately 1.8 atoms/cm3, turns into intense radiation that would quickly kill passengers and destroy electronic instrumentation. In addition, the energy loss of ionizing radiation passing through the ship’s hull represents an increasing heat load that necessitates large expenditures of energy to cool the ship. Stopping or diverting this flux, either with material or electromagnetic shields, is a daunting problem. Going slow to avoid severe H irradiation sets an upper speed limit of v ~ 0.5 c. This velocity only gives a time dilation factor of about 15%, which would not substantially assist galaxy-scale voyages. diffuse interstellar H atoms are the ultimate cosmic space mines and represent a formidable obstacle to interstellar travel.

关键词： Interstellar Travel Spaceflight Relativistic Spaceflight Space Travel Radiation

Axonal Conduction Velocity: A Computer Study

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Journal of Applied Mathematics and Physics 2024年第1期12卷 60-71页

作者： arthur d. Snider Aman Chawla Salvatore d. Morgera department of Electrical Engineering University of South Florida Tampa USA department of Computer Science and Engineering Indian Institute of Technology New Delhi India

This paper derives rigorous statements concerning the propagation velocity of action potentials in axons. The authors use the Green’s function approach to approximate the action potential and find a relation between ... 详细信息

关键词： Neuron Axon Action Potential Conduction Velocity Internode

Effects of colored noise on the dynamics of quantum entanglement of a one-parameter qubit-qutrit system

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Chinese Physics B 2022年第5期31卷 141-149页

作者： Odette Melachio Tiokang Fridolin Nya Tchangnwa Jaures diffo Tchinda arthur Tsamouo Tsokeng Martin Tchoffo Research Unit of Condensed Matter Electronic and Signal ProcessingDepartment of PhysicsDschang School of Sciences and TechnologyUniversity of DschangPO Box:67 DschangCameroon Material Science Research Group Physics LaboratoryDepartment of PhysicsPost Graduate SchoolUniversity of MarouaPO Box:814 MarouaCameroon Centre d’Etudes et de Recherches en Agronomie et en Biodiversite Faculte d’Agronomie et des Sciences AgricolesUniversite de DschangCameroun

We analyzed the effect of colored noise on the negativity dynamics of a hybrid system consisting of a qubit-qutrit and not interacting,prepared from the start in an entangled one-parameter state and acting with noise in local and non-local *** this pink and brown noise we investigated two different situations:in the first situation,the noise is produced by a bistable oscillator with an unknown exchange rate;however,in the second situation,the noise is generated by a set of bistable *** found that entanglement decreases with time to zero,and undergoes the phenomenon of sudden death and *** pink noise is more prone to entanglement than the brown noise and the non-local environment is more prone to entanglement than the local *** the number of fluctuators is increased,entanglement decays faster and finally,for certain parameters of the initial state,the subsystems are not affected by the noise.

关键词： entanglement hybrid system qutrit colored noise

Septic arthritis of the hand:Current issues of etiology,pathogenesis,diagnosis,treatment

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World Journal of Orthopedics 2022年第7期13卷 622-630页

作者： Konstantin V Lipatov arthur Asatryan George Melkonyan Aleksandr d Kazantcev Ekaterina I Solov'eva Urii E Cherkasov department of General Surgery Institute of Clinical Medicine named after N.V.SklifosovskySechenov First Moscow State Medical University(Sechenov University)Moscow 119021Russia Wound and Wound Infection Surgery State Budgetary Institution“City Clinical Hospital named after S.S.Yudin of Moscow Healthcare Department”Moscow 115446Russia department of General Surgery Physician of The Hospital for War Veterans No 3Moscow 129336Russia department of General Surgery I.M.Sechenov First Moscow State Medical UniversityMoscow 119048Russia

Septic arthritis of the hand is a serious disease that often results in dysfunction of the joint or even the need to perform amputation of the *** rank second in the frequency of occurrence after lesions of the knee *** points concerning the etiology,the timing of the development of cartilage destruction and the development of osteomyelitis,approaches to surgical treatment,the duration of antibiotic therapy,and the start of rehabilitation measures remain the subject of numerous *** on a search in the PubMed,Web of Science and Google Scholar databases down to 1990-2021,publications on septic arthritis of the hand were found and *** following inclusion criteria were used in our review:(1) Septic arthritis of the hand;(2) Published in a peer review journal;(3) Written in English;and(4) Full text version *** were excluded if they met any of the following criteria:(1) Letters;(2) Articles published in abstract form only;and(3) Cadaveric *** arthritis of the hand was characterized by the most frequent damage to the joints of the index and middle fingers(> 50% of cases).Up to 90% of cases,the infection enters the joint as a result of penetrating trauma,animal bites,*** aureus became the most frequently isolated microorganism(30%-55%),and its polyantibiotic-resistant form Methicillin-resistant Staphylococcus aureus was found,according to various sources,from 0% to 73% among all isolated Staphylococcus *** arthritis,Pasteurella multocida(6%-11%) is often isolated as a result of animal *** cartilage destruction in the experiment developed within 24-48 h after *** clinical studies,the development of osteomyelitis was noted when treatment was delayed by more than 10 d.X-ray data during the first two weeks were *** of surgical treatment of septic *** and surgical treatment,and with the development of osteomyelitis,the implementation of arthro

关键词： Septic arthritis Hand Staphylococcus aureus Metacarpophalangeal joint Interphalangeal joint Rehabilitation

Renal functional outcomes are not adversely affected by selective angioembolization following percutaneous nephrolithotomy

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Asian Journal of Urology 2017年第1期4卷 27-30页

作者： Ricardo Palmerola Vinay Patel Christopher Hartman Chris Sung david Hoenig arthur d.Smith Zeph Okeke Smith Institute for Urology Northwell HealthNew Hyde ParkNYUSA Interventional Radiology Northwell HealthNew Hyde ParkNYUSA

Objective:Selective angioembolization(SAE)effectively diagnoses and treats iatrogenic vascular complications following percutaneous nephrolithotomy(PCNL).Methods:We retrospectively reviewed 1329 consecutive PCNLs and identified patients who underwent SAE following PCNL with at least 12-month *** glomerular filtration rate(eGFR)was calculated for all patients preoperatively,postoperatively and at last followup.A 1:2 matched cohort analysis was ***:Twenty-three patients underwent SAE and matched to 46 *** was no statistically significant difference in preoperative,postoperative,and follow-up eGFR when comparing patients who underwent SAE and those with an uneventful ***:Long-term eGFR is comparable in patients who undergo uncomplicated PCNL and those requiring SAE.

关键词： Selective angioembolization Percutaneous nephrolithotomy Urologic complications Contrast induced nephropathy Postoperative hemorrhage

High Oxygen Nanocomposite Barrier Films Based on Xylan and Nanocrystalline Cellulose

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Nano-Micro Letters 2010年第4期2卷 235-241页

作者： Amit Saxena Thomas J.Elder Jeffrey Kenvin arthur J.Ragauskas School of Chemistry and Biochemistry Georgia Institute of Technology USdA-Forest Service Southern Research Station Micromeritics Instrument Corporation

The goal of this work is to produce nanocomposite film with low oxygen permeability by casting an aqueous solution containing xylan,sorbitol and nanocrystalline *** morphology of the resulting nanocomposite films was examined by scanning electron microscopy and atomic force microscopy which showed that control films containing xylan and sorbitol had a more open structure as compared to xylan-sorbitol films containing sulfonated nanocrystalline *** average pore diameter,bulk density,porosity and tortuosity factor measurements of control xylan films and nanocomposite xylan films were examined by mercury intrusion porosimetry *** films reinforced with nanocrystalline cellulose were denser and exhibited higher tortuosity factor than the control xylan *** xylan films had average pore diameter,bulk density,porosity and tortuosity factor of 0.1730 μm,0.6165 g/ml,53.0161% and 1.258,respectively as compared to xylan films reinforced with 50% nanocrystalline cellulose with average pore diameter of 0.0581 μm,bulk density of 1.1513 g/ml,porosity of 22.8906% and tortuosity factor of *** transmission rate tests demonstrated that films prepared with xylan,sorbitol and 5%,10%,25% and 50% sulfonated nanocrystalline cellulose exhibited a significantly reduced oxygen permeability of 1.1387,1.0933,0.8986 and 0.1799 cm^3×μm/m^2×d×k Pa respectively with respect to films prepared solely from xylan and sorbitol with a oxygen permeability of 189.1665 cm^3×μm/m^2×d×k *** properties suggested these nanocomposite films have promising barrier properties.

关键词： Nanocomposites Xylan Nanocrystalline cellulose Oxygen barrier