Ex Parte Shifrin

Patent Trial and Appeal Board

Nov 30, 2016

13016733 (P.T.A.B. Nov. 30, 2016)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/016,733 01/28/2011 Lazar A. Shifrin 365188-991061 5153
26379 7590 12/02/2016
DLA PIPER LLP (US )
2000 UNIVERSITY AVENUE
EAST PALO ALTO, CA 94303-2248
EXAMINER
SIRIPURAPU, RAJEEV P
ART UNIT PAPER NUMBER
3737
NOTIFICATION DATE DELIVERY MODE
12/02/2016 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
PatentDocketingU S -Palo Alto @ dlapiper. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte LAZAR A. SHIFRIN1
Appeal 2015-003135
Application 13/016,733
Technology Center 3700
Before DONALD E. ADAMS, JEFFREY N. FREDMAN,
and TIMOTHY G. MAJORS, Administrative Patent Judges.
PER CURIAM
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a method
for digitally controlling the gain of an ultrasonic signal which have been
rejected as indefinite and obvious. We have jurisdiction under 35 U.S.C.
§ 6(b).
We affirm.
1 Appellant identifies the Real Party in Interest as Supertex, Inc. (App. Br.
1.)
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Application 13/016,733
STATEMENT OF THE CASE
Appellant’s “invention relates generally to low noise amplifiers
having operatively digitally controllable gain. Specifically, the invention
relates to digitally controllable variable-gain amplifiers and more
particularly to such amplifiers used in ultrasound imaging.” (Spec. p. 1.)
Claims 1, 3—6, and 15—20 are on appeal. Claim 1 is illustrative:
1. A method for digitally controlling the gain of an ultrasonic
signal comprising the steps of:
transmitting an ultrasonic signal into an insonified object;
receiving at least one echo ultrasonic signal of the
transmitted ultrasonic signal from scattering of the transmitted
ultrasonic signal within different depths of the object; and
compensating the attenuation of the received echo
ultrasonic signals from different depths of the object by
progressively increasing the gain during the reception of the
received echo ultrasonic signals as the signal penetrates deeper,
wherein the compensating includes:
supplying the received echo ultrasonic signal in
parallel to a plurality of N transconductor cells, wherein
each of said transconductor cells comprise a differential
pair of MOS transistors;
performing conversion of the received echo signal
to a plurality of N binary-weighted current signals;
switching, via a T-switch of each cell of the
plurality of N transconductor cells while keeping a
constant bias current, the conversion ON and OFF in
response to a control signal, wherein the control signal is
supplied from a look-up-table (LUT);
summing the current signals over all cells to form a
summed current signal; and
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converting the summed current signal to a voltage
signal.
(App. Br. 8 (Claims App’x).)
The claims stand rejected as follows:
I. Claims 6 and 19 under 35 U.S.C. § 112, second paragraph, as
being indefinite.
II. Claims 1, 3—6, and 15—20 under 35 U.S.C. § 103(a) over
Torrence,2 Gibson,3 Hirvilampi,4 Gilbert,5 Guckenberger,6 Tam,7 and
Brindle.8
REJECTION I
Claims 6 and 19 recite “wherein transconductance of a differential
pair is by selecting at least one of, an appropriate bias current and transistor
aspect ratio.” (App. Br. 9—10 (Claims App’x).)
The Examiner determines that “the claims appear incomplete and are
grammatically flawed to an extent that a skilled artisan cannot understand
the meaning of the current claim language.” (Final Act. 2.)
Appellant contends
One of ordinary skill in the art, after reading the
specification and file history, would understand that the phrases
of claims 6 and 19 each mean that the transconductance of a
differential pair is defined or determined by selecting an
2 Torrence, US 4,733,668, issued Mar. 29, 1988.
3 Gibson et al., US 2002/0011897 Al, published Jan. 31, 2002.
4 Hirvilampi et al., US 6,614,299 B2, issued Sept. 2, 2003.
5 Gilbert, US 5,077,541, issued Dec. 31, 1991.
6 Guckenberger et al., US 7,042,295 B2, issued May 9, 2006.
7 Tam, US 5,910,780, issued June 8, 1999.
8 Brindle, US 2004/0113746 Al, published June 17, 2004.
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appropriate bias current and/or transistor aspect ratio. For
example, paragraph 0047 of the specification states: “[Tjhere are
two ways to varying the transconductance of a differential pair,
namely, by appropriate selecting the bias current 10 or the
transistor aspect ratio W/L.”
(App. Br. 5; see also Reply Br. 2.)
We are not persuaded.
“[Djuring patent prosecution when claims can be amended,
ambiguities should be recognized, scope and breadth of language explored,
and clarification imposed.” In re Zletz, 893 F.2d 319, 321 (Fed. Cir. 1989).
As the Examiner explains, “Appellant in reading words into the claim
language[,] provide[s] two alternative readings, defining and determining”
and “a skilled artisan would not know if the values were actively defined or
passively determined after the fact based on Appellant’s arguments, claim
language, and disclosure.” (Ans. 2—3.)
We thus affirm the rejection of claims 6 and 19 as being indefinite.
REJECTIONII
Appellant does not argue the claims separately. We select claim 1 as
representative.
The Examiner finds that
Torrence discloses a method for controlling the gain of an
ultrasonic signal comprising the steps of: (a) transmitting an
ultrasonic signal into an insonified object (see Figs. 2, 5, and 8,
col 1 In 30-50, col 3 In 17—39, col 4 In 9-33, and col 5 In 4—54);
(b) receiving echo ultrasonic signals of said transmitted
ultrasonic energy signal from scattering of said transmitted
ultrasonic energy signal within said object (see Figs. 2, 5, and 8,
col 1 In 30-50, col 3 In 17—39, col 4 In 9-33, and col 5 In 4—54);
and (c) compensating the attenuation of said echo ultrasonic
signal from different depths by progressively increasing the gain
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during the reception of said echo ultrasonic signals as the signal
penetrates deeper, to make the intensity of the signal propagating
through the object, approximately constant (see Figs. 2, 5, and 8,
col 1 In 30-50, col 3 In 17—39, col 4 In 9-33, and col 5 In 4—54).
(Final Act. 3.)
The Examiner finds that
Gibson discloses a similar method of varying gain, wherein (c)
further comprises the steps of: (a) supplying a received voltage
echo signal in a parallel to a plurality of N transconductor cells
wherein each of said transconductor cell comprising a
differential pair of MOS transistors (see Figs. 1—3 and para 5,
12—17, 20, and 38—44, noting that MOS transistors are well
known in the art and are disclosed or would be obvious in light
of Gibson); (b) converting said voltage echo signal to a plurality
of N binary-weighted current signals (see Figs. 1—3 and para 5,
12—17, 20, and 38—44); (c) accommodating each cell of said
plurality of N transconductor cells for switching the above step
of converting ON and OFF in response to a control signal (see
Figs. 1—3 and para 5, 12—17, 20, and 38-44); and (d) summing
said current signals over all cells to form a summed current signal
(see Figs. 1—3 and para 5, 12—17, 20, and 38-44).
{Id. at 3 4.)
The Examiner concludes that it would have been obvious
to have combined the teachings of Torrence with . . . Gibson
because doing so would provide proper variable gain for an
ultrasound device while using a circuit with minimal switches
and multiplexers, thus avoiding degradation in performance.
Further, the Gibson circuit provides programmable gain
operation over a wide range and constant bandwidth while
reducing noise and glitches.
{Id. at 4.)
The Examiner finds that “Gibson notes constant current bias sources
are utilized (see Figs. 1—3 and para[.] 5, 12—17, 20-29, and 38—44)” and
concludes that it would have been obvious “to optimize the bias currents,
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since it has been held that discovering an optimum value of a result effective
variable involves only routine skill in the art.” (Id.)
The Examiner finds that “Gibson does not specifically enumerate the
following steps[:] (e) converting the summed current signal to a voltage
signal and (f) supplying said control signals to each of the transconductor
cells from a look-up-table (LUT).” (Id.)
The Examiner determines that
back converting the current signal to a voltage signal is well
known in the art. For example, Gilbert discloses a similar circuit
wherein an additional amplifier is placed after the circuit for
additional amplification and conversion of the signal from
current back to a voltage signal (see Figs. 1—3). It would have
been obvious to a skilled artisan to have included said additional
element for the purpose of additional amplification and the
conversion of the signal back to a voltage signal.
(Id. at 5.)9
The Examiner finds that “Gibson discloses an enable signal but does
not specifically enumerate how said signal is generated.” (Id.)
The Examiner turns to Hirvilampi and finds that it “discloses a similar
amplification method, wherein the control signal is provided using a look­
up-table (LUT).” (Id.) According to the Examiner, the “combination of
Hirvilampi and Torrence teaches to a skilled artisan to provide the LUT of
Hirvilampi with the time-gain curves of Torrence.” (Id.)
The Examiner concludes that it would have been obvious “to have
combined the device of Torrence and Gibson with the further teachings of
9 Examiner cites Guckenberger as additional or alternative prior-art evidence
for converting current and voltage signals. (Final Act. 5.)
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Hirvilampi because doing so would provide accurate timing by sending a
variety of control signals to account for possible operating conditions.” (Id.)
The Examiner finds that Tam and Brindle evidence further switching
features (id. at 6.); Appellant does not dispute these findings on appeal.10
The issue with respect to this rejection is: Does the evidence of
record support the Examiner’s conclusion that Torrence, Gibson, Hirvilampi,
Gilbert, Guckenberger, Tam, and Brindle, render claim 1 obvious?
Findings of Fact
The Examiner’s findings concerning the scope and content of the prior
art may be found at pages 3—7 of the Final Action dated March 21, 2014.
(See also Ans. 3—7.) We provide the following findings for emphasis.
1. Torrence teaches that
body tissues on the average attenuate ultrasound energy at a rate
of approximately 1 dB[]/mHz/cm. To compensate for this rapid
attenuation, prior art ultrasound systems generally incorporate
circuitry (termed “time-gain compensation” or TGC circuitry)
which acts to increase receiver gain during a time period which
follows the introduction of a pulse into the body. The time
required for reflected pulses to return to the receiver is a direct
function of the depth of a reflecting structure within the body;
thus receiver gain is automatically increased for reflected pulses
which originate deep within the body. The attenuation of
ultrasound energy is, however, not uniform for all body tissues
and structures.
(Torrence 1:30-43; see also Final Act. 3.)
10 Appellant contends only that “Gibson, Hirvilampi, Gilbert, Tam, Brindle,
and Guckenberger do not discuss or apply to ultrasound devices at all.”
(App. Br. 6.)
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2. Torrence teaches that “the gain of the receiver ... is controlled
by an electrical signal which is furnished by a time-gain control (TGC)
circuit... to compensate for the attenuation of ultrasound energy which is
reflected from structures at varying depths in the body.” (Torrence 3:18—22;
see also Final Act. 3.)
3. Torrence teaches
the slope of the time-gain compensation applied to the receiver
in a diagnostic ultrasound system is caused to vary with time to
match the attenuation characteristic of tissue at depths
corresponding to those times. . . . The break point ... in the
time-gain compensation curve, may, in the case of body wall
compensation, be set to occur at a fixed time (following
transmission of the pulse) which corresponds to the approximate
thickness of the body wall. This time may be set at a nominal
value determined from previous experience or may be set by
reference to the echo which occurs at the interface between the
body wall and the internal body tissues.
(Torrence 4:15—33; see also Final Act. 3.)
4. Figure 1 of Gibson is reproduced below:
FIG. 1
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Figure 1 shows
[a] programmable gain amplifier (10) has a differential input
(12—13), a differential output (16—17), and a plurality of enable
inputs (21, 31—34). The amplifier includes a plurality of
transconductor sections (26—29), which each have input nodes
coupled to the differential input, output nodes coupled to the
differential output, and an enable node coupled to a respective
enable signal.
(Gibson Abstract; see also Final Act. 3 4.)
5. Figure 2 of Gibson is reproduced below:
FIG, 2
Figure 2 shows that
[t]he transconductor sections have different gains, which are
respective powers of two. Each transconductor section includes
a transconductor circuit (51, 56) which is coupled in series with
at least one current mirror circuit (52—53, 57—58). Each
transconductor circuit has a transistor (121) with a class A
quiescent current that is proportional to the corresponding gain,
the transistor being sized to achieve an optimum current density
for its quiescent current. Each such transistor has two terminals
coupled to other circuitry within the transconductor circuit, and
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Application 13/016,733
a third terminal coupled only to the associated current mirror
circuit.
(Gibson Abstract; see also Final Act. 3 4.)
6. Gibson teaches
Each of the transconductor sections 26—29 is respectively
enabled and disabled when the corresponding one of the lines
31—34 of the bus 21 respectively has logic low and logic high
states. When disabled, each transconductor section 26—29
effectively has its output disabled, so that its output has no effect
on the differential output 16—17. Each of the transconductor
sections 26—29, when enabled, accepts a differential voltage from
the differential input 12—13, and outputs a differential current to
the differential output 16—17. Since the transconductor sections
26—29 each output a current rather than a voltage, the currents
from the transconductor sections which are enabled are
effectively summed, in order to produce the total output current
that appears at the differential output 16—17. In contrast, the
transconductor sections which are disabled do not contribute to
or affect the current produced at the differential output 16—17 by
the enabled transconductor sections.
(Gibson 113; see also Final Act. 3^4.)
7. Gibson teaches that “the programmable gain amplifier 10 is
implemented in the form of an integrated circuit, which facilitates
fabrication of certain components such as transistors.” (Gibson 117; see
also Final Act. 3^4.)
8. Gibson teaches that “the outputs of the various transconductor
sections can be directly connected together, in order to generate the final
output signal, while avoiding multiplexers or other switches in the signal
path, and the degradation in performance associated with them.” (Gibson
141; see also Final Act. 3^4.)
9. Gibson teaches that “the transconductor sections 26—29 of FIG.
1 each have another operational mode, in which they are disabled by the
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corresponding line EN(n) of the enable bus 21.” (Gibson 142; see also id.
at 143, Final Act. 3—4.)
10. Hirvilampi teaches
A method and system to balance a signal through a
plurality of parallel amplifier elements of an amplifier device.
An input signal to the amplifier device is divided substantially
equally among a plurality of parallel amplifier elements. A
signal through each of the amplifier elements is measured. If any
of the measured signals deviates by a predetermined threshold
from a reference signal, an adjustment to an input parameter to a
tuning circuit associated with the particular amplifier element is
determined. The determined adjustment is applied to the
particular a tuning circuit to appropriately adjust the output of the
deviating amplifier element. The output of the plurality of
amplifier elements is combined as the total output of the
amplifier device.
(Hirvilampi Abstract; see also Final Act. 5.)
11. Hirvilampi teaches
The adjustment control circuit. . . may optionally include
a look up table (TUT) to store parameter values or adjustments
(for transmittal to parameter tuning circuits []) correlated to
differences calculated by the signal comparison circuit.... The
look-up table may, for example, contain adjustments that are
dependent upon signal frequency, power level, and/or ambient
temperature. Each of the parameter tuning circuits [] then
correspondingly adjusts its respective portion of the input signal
that is received from the power divider [] and transmits this
adjusted input signal portion to its respective amplifier element
[] so as to adjust the output of that amplifier element [].
(Hirvilampi 5:59-6:4; see also Final Act. 5.)
DISCUSSION
We adopt the Examiner’s findings of fact and reasoning regarding the
scope and content of the prior art (Final Act. 3—7; Ans. 3—7; FF 1—11) and
agree that claim 1 would have been obvious over Torrence, Gibson,
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Hirvilampi, Gilbert, Guckenberger, Tam, and Brindle. We address below
Appellant’s arguments.
Appellant contends that “there is no disclosure in Gibson of a received
voltage echo signal. In fact, Gibson did not involve echo signals at all
because its technology involved a cable modem driver and not an ultrasound
imaging device.” (App. Br. 5; see also Reply Br. 4.)
This argument is unpersuasive and fails to account for Torrence,
which teaches, inter alia, that “[t]his time may be set at a nominal value
determined from previous experience or may be set by reference to the echo
which occurs at the interface between the body wall and the internal body
tissues.” (FF 3; see also FF 1—2.) “Non-obviousness cannot be established
by attacking references individually where the rejection is based upon the
teachings of a combination of references []. [The reference] must be read,
not in isolation, but for what it fairly teaches in combination with the prior
art as a whole.” In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986).
Appellant argues that Hirvilampi “does not teach using the look-up-
table as the basis for turning conversions on and off, nor does it teach using
a look-up-table for doing that specifically to compensate the attenuation of a
received echo ultrasonic signal.” (App. Br. 5; see also Reply Br. 5.)
Appellant also contends that “Hirvilampi certainly does not teach a look up
table of time-gain curves.” (App. Br. 6.)
These arguments are unpersuasive. Gibson teaches that “the
transconductor sections 26—29 of FIG. 1 each have another operational
mode, in which they are disabled by the corresponding line EN(n) of the
enable bus 21.” (FF 9.) Gibson teaches that “[e]ach of the transconductor
sections 26—29 is respectively enabled and disabled when the corresponding
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one of the lines 31—34 of the bus 21 respectively has logic low and logic
high states.” (FF 6; see also FF 4—5, 7—8; Ans. 5—6.) Torrence teaches
“[t]he break point... in the time-gain compensation curve, may, in the case
of body wall compensation, be set to occur at a fixed time (following
transmission of the pulse) which corresponds to the approximate thickness
of the body wall.” (FF 3.) Here again, Appellant’s contentions are
unpersuasive because they do not adequately grapple with the rejection as
presented — based on the combination of Hirvilampi with the teachings of
Gibson and Torrence.
Appellant contends that “reading Torrence, Gibson, and Hirvilampi
does not lead one to the solution of using a look-up table to provide a control
signal for turning transconductors on and off to compensate for the
attenuation of a received echo ultrasonic signal.” (App. Br. 6).
We are not persuaded. As the Examiner explains,
a skilled artisan would have found it a common place expedient
to store the time-gain curves of Torrence to control the amplifier
of Gibson in a LUT as taught by Hirvilampi. Essentially,
Hirvilampi discloses that control data must be stored and that
said data can be stored in a LUT. Storing the time-gain curves
of Torrence in a LUT would have predictably stored data for later
use by an amplifier circuit. The combination of references
discloses storing time-gain curve data used for amplifying an
ultrasound signal via the Gibson circuit in a LUT.
(Ans. 5—6.)
Appellant fails to establish an evidentiary basis on this record to show
that the Examiner’s rejection is something other than “the predictable use of
prior art elements according to their established functions.” KSR Int 7 Co. v.
Teleflex Inc., 550 U.S. 398, 417 (2007). See also In re Geisler, 116 F.3d
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1465, 1470 (Fed. Cir. 1997) (“[Attorney argument [is] not the kind of
factual evidence that is required to rebut a prima facie case of obviousness”).
Appellant argues that “Gibson, Hirvilampi, Gilbert, Tam, Brindle, and
Guckenberger do not discuss or apply to ultrasound devices at all. Thus,
they are not within the relevant field, and one of ordinary skill in the art
would not have combined them together with Torrence to achieve a solution
in the field of ultrasound devices.” (App. Br. 6—7.)
This argument is also unpersuasive. We agree with the Examiner that
the field of ultrasound imaging requires knowledge of myriad
circuits including amplifiers. Many ultrasound devices
necessarily require amplifiers to amplify faint signals and to
account for time and depth dependent imaging concerns.
Accordingly, a skilled artisan in the field of ultrasound imaging
would necessarily have knowledge of and consider the field of
amplifier circuits to be within the field of ultrasound imaging.
Moreover, the cited references also appear to be solving the same
problems Appellant has sought to solve in the same way.
Appellant is utilizing amplifiers and other circuits to amplify and
condition a signal in a circuit. Similarly, Gibson for example
uses a common place circuit to predictably amplify a signal.
Since amplifiers are a necessary component of ultrasound device
and a skilled artisan would have considered the field of
amplifiers to be included in the field of ultrasound imaging, the
cited art is analogous art. Further, the cited art is related to
Appellant’s problem to be solved.
(Ans. 6—7.) We further observe that Appellant’s Specification, in a section
titled “DESCRIPTION OF THE RELATED ART” describes prior art
amplifiers — some of which are not specific to ultrasound devices. (See,
e.g., Spec. 19 (referring to a Broadcom patent (US 7,425,866).). This is
consistent with the Examiner’s determination that the skilled artisan’s
knowledge of suitable amplifiers would not be limited to only those circuits
that the art expressly discloses have been put to use in ultrasound devices.
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Absent persuasive evidence or argument to the contrary, we agree with the
Examiner that the skilled artisan would have predictably used or modified
the amplifiers of the cited art to design improved ultrasound devices.
Appellant contends that “[although Torrence does indicate the need
for amplification, it does not even hint at using the type of amplification
described in claims 1 and 15, nor does it point toward the type of amplifier
described in Gibson,” and that “[t]he important inquiry is whether Gibson
teaches an amplifier that is appropriate for the system and problem
attempted to be solved by Torrence. There is nothing in the Record that
suggests that is the case.” (Reply Br. 4—5.)
These arguments are unpersuasive.
[EJvidence of a motivation to combine need not be found in the
prior art references themselves, but rather may be found in “the
knowledge of one of ordinary skill in the art or, in some cases,
from the nature of the problem to be solved.” .. . When not from
the prior art references, the “evidence” of motive will likely
consist of an explanation of the well-known principle or
problem-solving strategy to be applied.
Dystar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., 464
F.3d 1356, 1366 (Fed. Cir. 2006) (emphases in original, quoting In re
Dembiczak, 175 F.3d 994, 999 (Fed. Cir. 1999)). The Examiner has
provided explanation and persuasive reasoning sufficient to support a prima
facie case of obviousness. KSR, 550 U.S. 398, 418 (2007) (holding that the
conclusion of obviousness must be supported with “some articulated
reasoning with some rational underpinning.”)
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CONCLUSION OF LAW
We affirm the rejection of claims 6 and 19 under 35 U.S.C. § 112,
second paragraph, as being indefinite.
We affirm the rejection of claims 1, 3—6, and 15—20 under 35 U.S.C.
§ 103(a) over Torrence, Gibson, Hirvilampi, Gilbert, Guckenberger, Tam,
and Brindle.
TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED
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