Pathophysiology, nursing role transition, philosophy, evolution,

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Parts  6 and 7  have the same questions. However, you must answer with references and different writing, always addressing them objectively, as if you were different students. Similar responses in wording or references will not be accepted.

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__________________________________________________________________________________

Part 1: Pathophysiology

 

Pulmonary Function:
D.R. is a 27-year-old man, who presents to the nurse practitioner at the Family Care Clinic complaining of increasing SOB, wheezing, fatigue, cough, stuffy nose, watery eyes, and postnasal drainage—all of which began four days ago. Three days ago, he began monitoring his peak flow rates several times a day. His peak flow rates have ranged from 65-70% of his regular baseline with nighttime symptoms for 3 nights on the last week and often have been at the lower limit of that range in the morning. Three days ago, he also began to self-treat with frequent albuterol nebulizer therapy. He reports that usually his albuterol inhaler provides him with relief from his asthma symptoms, but this is no longer enough treatment for this asthmatic episode.

Case Study Questions

According to the case study information

1. Hhow would you classify the severity of D.R. asthma attack? (One paragraph)

2. Name the most common triggers for asthma in any given patients (One paragraph)

a. Specify in your answer which ones you consider applied to D.R. on the case study.

Based on your knowledge and your research

3. Explain the factors that might be the etiology of D.R. being an asthmatic patient (One paragraph)

Part 2: Pathophysiology

 

Answer the questions in a single paragraph. Make sure the number of words is similar.

Fluid, Electrolyte and Acid-Base Homeostasis:

Ms. Brown is a 70-year-old woman with type 2 diabetes mellitus who has been too ill to get out of bed for 2 days. She has had a severe cough and has been unable to eat or drink during this time. On admission, her laboratory values show the following:

  • Serum glucose 412 mg/dL
  • Serum sodium (Na+) 156 mEq/L
  • Serum potassium (K+) 5.6 mEq/L
  • Serum chloride (Cl–) 115 mEq/L
  • Arterial blood gases (ABGs): pH 7.30; PaCO2 32 mmHg; PaO2 70 mmHg; HCO3– 20 mEq/L

Case Study Questions

Based on Ms. Brown admission’s laboratory values

One paragraph

1. Could you determine what type of water and electrolyte imbalance does she has? explain

Based on your readings and your research

2. Define and describe Anion Gaps and its clinical significance.

One paragraph

3. Describe the signs and symptoms to the different types of water imbalance 

a. Describe clinical manifestation she might exhibit with the potassium level she has.

One paragraph

4. Which would be the most appropriate treatment for Ms. Brown and why?

One paragraph

5. What the ABGs from Ms. Brown indicate regarding her acid-base imbalance?

 

Part 3: Nursing Role Transition (Write in the first person)

 Role: Nurse

Unit: Dialysis

Include the role and unit of care in the answers to the questions

1. What makes a team effective in terms of achieving expected outcomes for the patients?  (One paragraph) 

2. What makes a team ineffective in terms of achieving expected outcomes for the patients?  (One paragraph) 

3. What is your input on your teamwork being effective? (One paragraph) 

4. Do your teamwork effective? why? (One paragraph) 

5. How can the nurses avoid being a part ineffective in the teamwork (One paragraph) 

Part 4: Nursing Role Transition (72 hours)

Role: ANP-certified registered nurse anesthetists

1. Abstract (One paragraph)

2. Introduction (One paragraph)

3. Describe the role (Two paragraphs)

4. Why are you becoming a Nurse Practitioner? (Write in the first person-– Two paragraphs)

Find one research article, expert opinion about the Nurse Practitioner role 

5. Summarize the article. (Two paragraphs)

6. What does the Institute Of Medicine (IOM) say about the need of Nurse Practitioners?  (One paragraph)

7. Describe the effects that you will have as an advanced practice nurse in terms of healthcare industry and patient outcomes. (Write in the first person-Two paragraphs)

8. Conclusion (One paragraph)

Part 5:  Philosophy/Critical Thinking

Answer the questions in a single paragraph. Make sure the number of words is similar.

According to the movie, Wit

One paragraph

1. Describe the involvement of nurse Susy with the main character of the movie.

2. Compare what could you have done differently? Write in the first person

One paragraph

3. Discuss the family dynamic and how this affects the main character.

4. Discuss the nurse’s action and how this impacts the relationship with the patient

One paragraph- Writ in the first person

5. In your opinion, do you think that the nurses working with the patient posse a strong work ethic? Give examples.  Write in the first person- 

Parts  6 and 7  have the same questions. However, you must answer with references and different writing, always addressing them objectively, as if you were different students. Similar responses in wording or references will not be accepted.

Part 6: Evolution, Taxonomy, and Phylogeny

Watch the following videos on evolution, taxonomy and phylogeny and understand how they are related to one another. Then, read the following scientific article by Donley et al. (2004) (see part 6 and 7 File) and answer 

The pap3r discusses similarities between lamnid sharks and tunas. Lamnids, sharks belonging to the family Lamnidae such as Carcharodon carcharias and Isurus oxyrinchus

1. All have which taxonomic groupings in common?

2. Explain the concept of convergent evolution as discussed in the article. 

a. Provide a correctly cited example of one other pap3r that discusses convergent evolution between these taxonomic groups. 

Scientific literature often involves approaching complicated topics with terms or concepts you have never encountered before. 

3. Provide an example of something the article you found interesting but were unfamiliar with prior to reading. 

a. Discuss ways you find it helpful to approach these complex subjects when reading a pap3r.

Part 7: Evolution, Taxonomy, and Phylogeny

Watch the following videos on evolution, taxonomy and phylogeny and understand how they are related to one another. Then, read the following scientific article by Donley et al. (2004) (see part 6 and 7 File) and answer 

The pap3r discusses similarities between lamnid sharks and tunas. Lamnids, sharks belonging to the family Lamnidae such as Carcharodon carcharias and Isurus oxyrinchus

1. All have which taxonomic groupings in common?

2. Explain the concept of convergent evolution as discussed in the article. 

a. Provide a correctly cited example of one other pap3r that discusses convergent evolution between these taxonomic groups. 

Scientific literature often involves approaching complicated topics with terms or concepts you have never encountered before. 

3. Provide an example of something the article you found interesting but were unfamiliar with prior to reading. 

a. Discuss ways you find it helpful to approach these complex subjects when reading a pap3r.

 

Part 8: Nursing leadership

1. Explain why leaders are made and are not born (Three paragraphs)

 

Part 9: Nursing Leadership

1. Define what is meant by strength-based leadership in nursing (One paragraph)

2. Give one profound/complete example of strength-based leadership in nursing (One paragraph)

3. What characteristics have the nurses capable of demonstrating strength-based leadership (One paragraph)

Part 10: Nursing Leadershipwrite in the first person

Role: Nurse

Position to advocate: Patient

Situation: A head nurse who appeared to be intoxicated with alcohol physically abused an elderly woman while she was showering her. The nurse became aware of the behavior of the head nurse.

Nursing should be an advocate for themself, their client, and their profession. 

1. Describe the situation daily

2. Describe your position

3. How did you deal with the situation as a leader nurse?

Part 11: Nursing philosophy (Write in the first person)

1. Introduction (One paragraph)

2. What is your idea of what a nurse should be? (One paragraph)

3. Why do you want to be a nurse? (One paragraph)

4. How do you identify with the feelings of others? (One paragraph)

5. How do you plan to handle conflict amongst your patient and their family members? (One paragraph)

6. Do you enjoy and find fulfillment in serving others? (One paragraph)

Role: Nurse

……………………………………………………..

Convergent evolution in mechanical
design of lamnid sharks and tunas
Jeanine M. Donley1, Chugey A. Sepulveda1, Peter Konstantinidis2,
Sven Gemballa2 & Robert E. Shadwick1

1Marine Biology Research Division, Scripps Institution of Oceanography,
University of California San Diego, La Jolla, California 92093-0202, USA
2Department of Zoology, University of Tübingen, Auf der Morgenstelle 28,
D-72076 Tübingen, Germany
………………………………………………………………………………………………………………………………………………………..

The evolution of ‘thunniform’ body shapes in several different
groups of vertebrates, including whales, ichthyosaurs1 and sev-
eral species of large pelagic fishes2 supports the view that physical
and hydromechanical demands provided important selection
pressures to optimize body design for locomotion during ver-
tebrate evolution. Recognition of morphological similarities
between lamnid sharks (the most well known being the great
white and the mako) and tunas has led to a general expectation
that they also have converged in their functional design; however,
no quantitative data exist on the mechanical performance of the
locomotor system in lamnid sharks. Here we examine the swim-
ming kinematics, in vivo muscle dynamics and functional mor-
phology of the force-transmission system in a lamnid shark, and
show that the evolutionary convergence in body shape and
mechanical design between the distantly related lamnids and
tunas is muchmore than skin deep; it extends to the depths of the
myotendinous architecture and the mechanical basis for propul-
sive movements. We demonstrate that not only have lamnids and
tunas converged to amuch greater extent than previously known,
but they have also developed morphological and functional
adaptations in their locomotor systems that are unlike virtually
all other fishes.
During their 400 million years of independent evolution, sharks

and bony fishes have diverged in many fundamental aspects of their
anatomy and physiology. However, two groups of dominant open-
ocean predators, the lamnid sharks and the tunas, evenwhen looked
at superficially, display remarkably similar morphological special-
izations related to locomotion3–12 (Fig. 1a). The shared character-
istics in these distantly related groups that distinguish them from
virtually all other fish have arisen independently, probably as the
result of selection for fast and continuous locomotion. Moreover, in
both lamnids and tunas, the aerobic (red) musculature that powers
cruise swimming is concentrated in a more medial (closer to the

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William Sample
William Sample

backbone) and anterior position compared with the relatively
uniform and superficial position in other fishes; the body tempera-
ture is elevated above that of the surrounding water, facilitated by
counter-current heat exchangers associated with the internal red
muscle; and themuscle segments (myotomes) are highly elongated3.
Recent studies on tunas revealed a host of unique functional

adaptations in their locomotor system that distinguish tunas from

all other bony fishes4,13. Similar investigations on swimming lamnid
sharks are lacking because of the difficulty in handling such large
and dangerous predators; thus, the dynamic properties of the
lamnid locomotor system remain unknown. This paper presents
in vivo quantitative measurements of swimming kinematics and
muscle dynamics, and analysis of the morphology of the force-
transmission system in a lamnid shark.

First, we examined the kinematics of steady swimming in the
shortfinmako shark (Isurus oxyrinchus). Lateral displacement of the
dorsal midline as a function of body position was calculated from
dorsal video images of mako sharks swimming under controlled
conditions in a swim tunnel (Fig. 1b; see also Supplementary
Video). Descriptions of undulatory swimming modes in fishes are
based on the proportion of the body that participates in the lateral
thrust-producing movements14, and can be distinguished by differ-
ences in patterns of lateral displacement along the body, as shown in
Fig. 1c. Compared with other teleosts, tunas exhibit the least
undulatory (thunniform) mode of locomotion, in which lateral
movements are largely confined to the caudal region where body
mass is reduced by tapering. The lateral displacement data pre-
sented here show that the lamnid shark kinematically resembles
tuna more than other sharks15 or subcarangiform teleosts: the
degree of lateral motion along the mako shark’s body from ,0.4L
to ,0.8L (where L is total body length) is relatively small, demon-
strating that lamnids swim using a thunniform-like mode. The
amplitude of lateral motion increases substantially beyond ,0.8L
where the body tapers to the narrow caudal peduncle. Lamnids, like
tunas, have the least lateral motion in the mid-body region where
the bulk of the muscle resides and have a reduced body mass in the
caudal region where lateral amplitudes are high, both being features
that match predictions for enhancing hydromechanical efficiency of
swimming9.

Because lamnids have both internal red muscle and a thunni-
form-like swimmingmode, we tested the possibility that shortening
of the red muscle would be physically uncoupled from deformation
of the adjacent skin, backbone and white muscle, a unique func-
tional property of red muscle that has been observed so far only in
tunas. Whereas in most teleosts superficial red muscle fibres con-
tract sequentially to cause a posteriorly travelling wave of local body
bending16–18, the internal position of red muscle in tunas allows
them to abandon this pattern of undulation and adopt a novel
mechanism to project red muscle action to posterior regions of the
body4,19, thereby facilitating thunniform kinematics. In the mako
shark we used sonomicrometry to record instantaneous muscle
segment length changes during steady swimming as well as during
passive, simulated swimming movements induced under anaesthe-
sia. The temporal relationship between red and white muscle
shortening was measured to determine whether the action of
these two muscle masses is synchronized, as in most fish, or
uncoupled, as in tunas. During passive swimming movements,
peaks in red muscle strain (that is, relative length change) were in
phase with peaks in adjacent white muscle strain (Fig. 2a). Thus,
when the body bends passively red muscle shortens synchronously
with the surrounding white muscle and skin, as one would expect.
In contrast, during active swimming the peaks in red muscle strain
were delayed relative to peaks in white muscle strain (Fig. 2b). By
cross-correlation analysis we determined that the mean phase shift
between simultaneous recordings of red andwhitemuscle strainwas
90ms (or,10% of the tail-beat cycle), with one individual as high
as 174ms (,17% of tail-beat cycle). The observed phase shift
indicates that during steady swimming the red muscle is indeed
physically uncoupled from the surrounding tissues and contracts in
phase with body bending at a more posterior location.

On the basis of a wave velocity of about 1 l s21 in sharks
swimming with a tail-beat frequency of about 1Hz, the red muscle
in the mid-body region will be shortening in phase with bending of
the backbone 10–17% closer to the tail. A consequence is that

Figure 1 Features of thunniform body shape and patterns of lateral undulation during

steady swimming. a, Thunniform body shape in lamnid sharks25 (right) and tunas26 (left).

Note the highly streamlined fusiform body shape that minimizes pressure drag, stiff,

high-aspect-ratio hydrofoil caudal fin that produces thrust by a hydrodynamic-lift

mechanism, and dorsoventrally flattened and enlarged caudal keel that decreases drag

produced by lateral movement of the peduncle6–8. b, Dorsal image of steady swimming
I. oxyrinchus. Scale bar: 10 cm. c, Lateral displacement, relative to the amplitude of lateral
motion at the tail tip, versus axial position in the mako shark (n ! 5; red symbols), tuna

(red dashed line27), leopard shark (black solid line15) and subcarangiform teleosts

(black dashed line; modified from ref. 13). This graph emphasizes differences in

displacement in the mid-body where most of the variation among swimming modes

occurs. Comparison of the mako shark and tuna illustrates the similarity in their swimming

mode, where lateral undulations are largely confined to the caudal region, indicated by

shading in dorsal outlines. The reduction in lateral motion in the mid-body region afforded

by their internal red muscle and modified force-transmission system is evident when

comparing the mako shark and tuna to sharks and bony fishes with less-specialized

swimming modes such as the subcarangiforms shown here.

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during short portions of each contraction cycle the red muscle will
be lengthening while the adjacent white fibres are shortening, and
vice versa. The loose sheath of connective tissue that surrounds the
red muscle mass (see Fig. 3d) may facilitate this shearing. These
results are remarkably similar to those described in tunas, where the

deep red muscle shortens and transmits force and displacement to
more posterior regions of the body rather than effecting local
bending4,19. Thus, the same mechanism enables tunas and lamnid
sharks to swim with the relatively stiff-bodied thunniform mode of
propulsion; even though the bulk of aerobic muscle is located more

Figure 2 Simultaneous recordings of muscle strain (segment length change/mean length)
of red (red trace) and adjacent white (grey trace) muscle during passive simulated

swimming movements (a) and active steady swimming (0.5 l s21) (b) in the mako shark.

During active swimming, as verified by red muscle activity (EMG trace), shortening in the

red muscle is delayed relative to the white muscle and is therefore in phase with lateral

motion in more posterior positions.

Figure 3 Collagenous architecture of myosepta of I. oxyrinchus. a, Oblique view focusing

on the hypaxial part between 0.54L and 0.74L (coloured inset). The elongated anterior

pointing cone (AC) of one myoseptum is shown. It intersects with the red musculature

(pale red area) and contains the hypaxial lateral tendon (dark red). The hypaxial lateral

tendon extends between the tip of the anterior pointing cone and the ventral posterior

cone (VPC). The hypaxial lateral tendon of a more anterior myoseptum is also shown

without its myoseptal sheet. The anterior part of this tendon is cut at its intersection with

the transverse plane (blue). b, Excised area of myosepta between the anterior pointing
cone and ventral posterior cone flattened out under polarized light. Pathways of

collagenous structures are shown in white. The hypaxial lateral tendon extends between

the red arrows. Dashed line, excision line from vertebral axis; thick white line, excision line

from skin; dotted line, excision line from remaining dorsal part of the myosepta, equivalent

to the dotted line in a; white arrowheads, intersection line of myosepta and loose
connective tissue surrounding red muscle. c, d, Transverse sections of left side.
Concentric rings of myosepta indicate nesting anterior pointing cones. c, Fresh section,
0.6L, showing red muscle with sections of hypaxial lateral tendons (white) within the red

muscle. d, Histological section at 0.54L. Red muscle is separated from surrounding white

muscle by a sheath of loose connective tissue. Numbers 1–12 indicate anterior portions of

12 hypaxial lateral tendons present in red muscle, whereas numbers 13–24 indicate

posterior portions of 12 additional hypaxial lateral tendons present in white muscle,

meaning that a single tendon covers 24 segments. The inset shows a detailed view of red

muscle and hypaxial lateral tendons (stained orange).

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anteriorly than in less derived species, the lateral motion it produces
is primarily focused to the caudal region.
Our morphological investigations demonstrate that the anatomi-

cal specializations associated with the force-transmission system are
also convergent. We used a new combination of techniques to
explore the three-dimensional morphology of the tendinous con-
nective tissue linkages (myosepta) that transmit muscular forces to
the skin and backbone, and their relationship to the internal red
muscle in the mako shark.
In principle, the three-dimensional shape of myotomes and their

associatedmyosepta inmako sharks resembles the regular pattern in
gnathostome fishes20, which includes a main anterior cone and a
dorsal and ventral posterior cone (see Supplementary Fig. 1 for
myoseptal parts of gnathostomes andmako sharks). Additionally, in
mako sharks two secondary anterior cones are present at the dorsal-
and ventral-most part of the myoseptum. The redmuscle is situated
in the lower part of the main anterior cone (Fig. 3a; see also
Supplementary Fig. 1d, e) where its fibres insert into the collagenous
myoseptum. In particular, red muscle fibres insert into the anterior
half of a myoseptal tendon (Fig. 3a). This tendon runs from the tip
of the main anterior cone through the red muscle towards its end
within the white muscle at the ventral posterior cone (Fig. 3a, b). It
clearly represents the homologue of the hypaxial lateral tendon in
gnathostome fishes (Supplementary Fig. 1). In mako sharks, this
tendon is extremely prominent and elongated when compared
with other fishes. In fact, myoseptal tendons as long and as
distinct as those associated with the red muscle in the mako shark
have never been reported in any shark species. We measured
tendon lengths as long as 0.19L in the posterior region of the
body (Supplementary Fig. 1e). The sonomicrometric results
suggest that the action of the red muscle is directed posteriorly
along the body by 10–17%. The measured tendon lengths accord
well with the values predicted from sonomicrometry, suggesting
that the hypaxial lateral tendon is responsible for transmitting red
muscle forces posteriorly. The prominent tendons of the posterior
body are gradually developed along a rostrocaudal gradient from
shorter (,0.06L; Supplementary Fig. 1d) and less distinct hypax-
ial lateral tendons of anterior myosepta to longer tendons in the
posterior.
In tunas, distinct and elongated tendons have also been discov-

ered and have been hypothesized to transfer forces from the red
muscle to the axial skeleton, and thus provide the anatomical basis
for force transmission from the anterior to the caudal region21. As
in mako sharks, the available length measurements and sonomicro-
metric data are in good accordance (0.18L experimentally and 0.16L
morphologically)22. Although in tunas the primary force-transmit-
ting tendons are in the horizontal septum, in the mako shark, as in
other sharks23, we found the horizontal septum to be reduced in the
posterior half of the body. Instead, the primary linkage to the tail
appears to be the hypaxial lateral tendons. Interestingly, although
the posterior oblique tendons in tunas and hypaxial lateral tendons
in mako sharks provide the same function, they have different
anatomical origins.
Through distinct evolutionary pathways lamnid sharks and tunas

have converged on the same mechanical design principle, that of
having internalized red muscle associated with a highly derived
force-transmission system, two features that form the basis for their
thunniform swimming mode. Our study shows that not only have
the physical demands of the external environment sculpted the body
shapes of large pelagic cruisers, but also the internal physiology and
morphology of their complex locomotor systems has been fine-
tuned over the course of their evolution. A

Methods
Shortfinmako sharks (I. oxyrinchus, family Lamnidae) ranging in size from 80 to 112 cm L
(total body length) were collected by hook and line off the coast of Southern California and
transported to the laboratory facilities at Scripps Institution of Oceanography (SIO) in a

transport chamber equipped with circulating aerated sea water. Once at SIO, the sharks
were placed into a large 3,000-l swim tunnel for an acclimation period of several hours
before experimentation. All procedures in capture, maintenance and experimentation
followed the guidelines of the University of California, San Diego Institutional Animal
Care and Use Committee.

In vivo muscle dynamics
To examine the dynamics of red andwhitemuscle contractions during swimming, we used
electromyography (EMG) and sonomicrometry, a technique for measuring distances in
which piezoelectric crystals transmit and receive ultrasonic pulses. Pairs of
sonomicrometric crystals were implanted into the deep red and adjacent white muscle to
record instantaneous changes in muscle segment length (strain) during active periods of
steady swimming as well as during passive, simulated swimming movements induced
under anaesthesia. Surgery was performed on anaesthetized individuals partially
submerged in a seawater bath according to procedures described previously15. Crystal
pairs were implanted approximately 15mm apart along the longitudinal axis of the body
and the leads were loosely anchored to the skin with surgical sutures. To verify the passive
and active states of the redmuscle, electrical activity was recorded using pairs of electrodes
implanted approximately 2mm apart directly bisecting the crystal pairs. After surgery, the
sharks were placed into the swim tunnel and allowed to recover before data collection. In
the recovery period we recorded red and white muscle strain during passive, simulated
swimming movements induced by gentle side-to-side motions of the centre of mass that
generated body undulation. Additionally, we recorded and analysed 30–50
consecutive tail-beat cycles for each individual while the shark swam steadily at
approximately 0.5 l s21. To measure the relative timing of red and white muscle
strain (phase shift), a cross-correlation analysis was performed using waveforms
containing approximately ten consecutive tail-beat cycles. Mean phase shift presented
in the text represents a mean of five individuals. Sonomicrometric and EMG signals
were recorded at 500Hz.

To correlate measurements of local muscle activation and strain with patterns of body
bending, five mako sharks were videotaped while swimming against a current of known
velocity in the swim tunnel. To synchronize the collection of sonomicrometric, EMG and
video recordings, a flashing red diode was recorded in the video sequences and its
excitation voltage was recorded with the sonomicrometric and EMG data. Kinematic
analysis follows procedures described previously15,24.

Morphology
We used a combination of clearing and staining, microdissection, polarized light
microscopy, standard histology and computer-based three-dimensional reconstruction to
explore the three-dimensional morphology of the tendinous connective tissue linkages
(myosepta). A small body segment (0.54–0.55L) of a formalin-fixed mako specimen
(65 cm total length) was prepared for standard histology (paraffin embedding; Azan–
Domagk staining, slice thickness of 15 mm). The two remaining parts (0–0.54L and
0.55–1.00L) were carefully skinned, stained for cartilage with Alcian blue 8GX (Merck)
and then cleared according to a recently described procedure20. Microdissections on the
myoseptal system were carried out using fine microsurgery tools. Myosepta or parts of
myosepta from all body regions were removed subsequently. Three-dimensional shape of
the myosepta was documented by a camera lucida, and tendon lengths and rostrocaudal
extensions of complete myosepta were measured in situ. Removed myosepta were
photographed under polarized light to visualize the collagen fibre pathways and tendons
(Zeiss Stemi 2000C with Fuji X digital camera HC300Z; 1,000 £ 1,450 pixels).
Additionally, the distribution of red muscle and its relation to myoseptal cones along the
body was examined. A three-dimensional reconstruction was obtained from histological
sections. Major landmarks (vertebrae, neural arches, vertical septum, abdominal cavity,
tip of main anterior, secondary anterior and ventral posterior cone, sections of tendons,
position of red muscle) were digitized and aligned using SurfDriver 3.5.3. Maxon Cinema
4D (Release 6) was used for choosing an adequate perspective and rendering. The obtained
three-dimensional view was edited by Adobe Photoshop (final shading, adding of
myoseptal shape).

Received 23 January; accepted 25 February 2004; doi:10.1038/nature02435.

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Supplementary Information accompanies the paper on www.nature.com/nature.

Acknowledgements We thank A. Biewener, J. Gosline, J. B. Graham, S. Vogel and N. Holland for
discussion and reviews. Funding was provided by NSF and UC Regents.

Competing interests statement The authors declare that they have no competing financial
interests.

Correspondence and requests for materials should be addressed to J.D. ([email protected]).

i

letters to nature

William Sample
William Sample
  • Convergent evolution in mechanical design of lamnid sharks and tunas
    • Main
    • Methods
      • In vivo muscle dynamics
      • Morphology
    • Acknowledgements
    • References
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