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Cross sections for the reaction pp -• e + e~ have been measured at s = 8.9,12.4, and 13.0 GeV 2 . The cross sections have been analyzed to obtain the proton electromagnetic form factors in the timelike region. We find that GM(Q 2 ) OC q~Aoc 2 {q 2 ) for q 2 > 5 (GeV/c) 2 .The understanding of nucleon structure is one of the central problems of hadronic physics. Measurements of the electric and magnetic form factors, GE and GM> &S functions of the four-momentum transfer q 2 provide experimental information relating to the nucleon structure. A large body of precise data obtained primarily from elastic scattering of electrons by protons and deuterons now exists for these form factors, with the form factors of the proton known up to q 2 = 31 (GeV/c) 2 [1]. However these data are primarily for spacelike momentum transfers (q 2 < 0). Results for GM in the timelike region (s --q 2 c 2 > 0) exist only for a small interval near threshold, 4m 2 c 4 < s < 5.6 GeV 2 . These data include precise measurements recently obtained at the Low Energy Antiproton Ring (LEAR) facility at CERN from the reaction pp -• e + e~ [2]. For larger momentum transfers only upper limits have been established by earlier e + e~ -* pp and pp -> e + e~ experiments [3]. Perturbative QCD predicts [4] that for large momentum transfers Q A \GM\/^Pshould be nearly proportional to the square of the running coupling constant for strong interactions, OL 2 (q 2 ). Recent data [1] for large spacelike momentum transfers are in remarkable agreement with this prediction for q 2 as small as 5 (GeV/c) 2 . It is of great interest to find out if a similar behavior holds for timelike momentum transfers.In this Letter we present the results of our measurements of the cross section for the reactionat y/s = 3.0, 3.5, and 3.6 GeV. These measurements were made as a part of Fermilab experiment E-760, which is dedicated to the study of charmonium by resonant formation in pp annihilations [5]. The differential cross section for process (1) can be expressed in terms of the proton magnetic and electric form factors as [6] da _ 7ra 2 (hc) 2 d(cos<9*) SEP 4772 |G M | 2 (1 + cosV) + -^|O s | 2 sin 2^*where E and P are the center of mass energy and momentum of the antiproton, and 0* is the angle between the e~ and the p in the center of mass system.

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Electronic cooling has become a subject of interest in recent years due to the rapidly decreasing size of microchips while increasing the amount of heat flux that they must dissipate. Conventional forced air cooling techniques cannot satisfy the cooling requirements and new methods have to be sought. Jet cooling has been used in other industrial fields and has demonstrated the capability of sustaining high heat transfer rates. In this work the heat transfer under arrays of microjets is investigated. Ten different arrays have been tested using deionized water and FC40 as test fluids. The jet diameters employed ranged between 69 and 250μm and the jet Reynolds number varied from 73 to 3813. A maximum surface heat flux of 310W∕cm2 was achieved using water jets of 173.6μm diameter and 3mm spacing, impinging at 12.5m∕s on a circular 19.3mm diameter copper surface. The impinging water temperature was 23.1°C and the surface temperature was 73.9°C. The heat transfer results, consistent with those reported in the literature, have been correlated using only three independent dimensionless parameters. With the use of the correlation developed, an optimal configuration of the main geometrical parameters can be established once the cooling requirements of the electronic component are specified.

MicroRNAs (miRNAs) are strongly up‐regulated under pathological stress and in a wide range of diseases. In recent years, miRNAs are under investigation for their potential use as biomarkers in cardiovascular diseases. We investigate whether specific cardio‐miRNAs are overexpressed in heart samples from subjects deceased for acute myocardial infarction (AMI) or sudden cardiac death (SCD), and whether miRNA could help differentiate between them. Forty four cases of death due to cardiovascular disease were selected, respectively, 19 cases categorized as AMI and 25 as SCD. Eighteen cases of traumatic death without pathological cardiac involvement were selected as control. Immunohistochemical investigation was performed for CD15, IL‐15, Cx43, MCP‐1, tryptase, troponin C and troponin I. Reverse transcription and quantitative real‐time PCR were performed for miR‐1, miR‐133, miR‐208 and miR‐499. In AMI group, stronger immunoreaction for the CD15, IL‐15 and MCP‐1 antibodies was detectable compared with SCD and control. Cx43 showed a negative reaction with respect to the other groups. Real‐time PCR results showed a down‐regulation of all miRNAs in the AMI group compared with SCD and control. The selected miRNAs presented high accuracy in discriminating SCD from AMI (miR‐1 and miR‐499) and AMI from control (miR‐208) representing a potential aid for both clinicians and pathologists for differential diagnosis.

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