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Results for “segmentation clock”

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At least 253 records · Page 14Linked to original sources

PubMed1996

Intraocular lens implantation in eyes with Fuchs' heterochromic iridocyclitis.

PURPOSE: To evaluate the results of cataract surgery with intraocular lens (IOL) implantation in eyes with Fuchs' heterochromic iridocyclitis. SETTING: Saint-Victor Hospital, Amiens, France. METHODS: We reviewed the charts of 93 patients (94 eyes) with heterochromic iridocyclitis who had cataract extraction and IOL implantation by the same surgeon. In six patients, the IOL was placed in the anterior chamber; 9 received Binkhorst four-loop IOLs sutured at the 12 and 6 o'clock positions, and 79 received posterior chamber IOLs, 15 in the sulcus and 64 in the capsular bag. Follow-up was from 6 months to 10 years (mean 41 months). RESULTS: Precipitates on the IOL surface and white keratic precipitates were detected in 65.5% of eyes. Most eyes had minimal anterior segment activity. No severe uveitis was observed. The major problem, observed in 12.3% of the patients, was glaucoma. Best corrected postoperative visual acuity was 20/40 or better in 76.6% of eyes. CONCLUSION: Eyes with heterochromic iridocyclitis responded well to cataract extraction with IOL implantation. The restoration of satisfactory binocular vision justifies IOL implantation in patients with Fuchs' unilateral syndrome.

Adolescent↗

PubMed1994

Low cost Video Scaler and Gray Scale Integrator.

A hybrid digital/analog device capable of making high-resolution linear and area measurements from a standard monochromatic video image is described. The device is capable of dynamic as well as static data acquisition when used in conjunction with standard NTSC video recording equipment. Digital output allows for computer interfacing. Linear dimensions are obtained by electronically superimposing two horizontal and two vertical scaling lines on a video monitor. Each linear dimension has an eight-bit resolution and is displayed on the front panel with seven segment LED's. Eight-bit, digital-to-analog converters are also used to provide analog outputs. A measurement of the temporal deformation pattern of the accessory capsule surrounding a mechanoreceptor (Pacinian corpuscles) in response to vibratory displacements is demonstrated. Area measurements are obtained via a window comparator, a 6-MHz clock, and a 16-bit digital-to-analog converter. Data is only valid within the zone set by the scaling lines, allowing data regions to be isolated from noise, etc. The 16-bit digital signal measuring the area of interest is then converted for analog output. The measurement of the consensual pupillary reflex in response to full-field illumination (Ganzfeld) is given as an example.

Animals↗

PubMed2005

Spinal cord maps of spatiotemporal alpha-motoneuron activation in humans walking at different speeds.

Functional MRI (fMRI) imaging of motoneuron activity in the human spinal cord is still in its infancy, and it will remain difficult to apply to walking. Here we present a viable alternative for documenting the spatiotemporal maps of alpha-motorneuron (MN) activity in the human spinal cord during walking, similar to the method recently reported for the cat. We recorded EMG activity from 16 to 32 ipsilateral limb and trunk muscles in 13 healthy subjects walking on a treadmill at different speeds (1-7 km/h) and mapped the recorded patterns onto the spinal cord in approximate rostrocaudal locations of the motoneuron pools. This approach can provide information about pattern generator output during locomotion in terms of segmental control rather than in terms of individual muscle control. A striking feature we found is that nearly every spinal segment undergoes at least two cycles of activation in the step cycle, thus supporting the idea of half-center oscillators controlling MN activation at any segmental level. The resulting spatiotemporal map patterns seem highly stereotyped over the range of walking speeds studied, although there were also some systematic redistributions of MN activity with speed. Bursts of MN activity were either temporally aligned across several spinal segments or switched between different segments. For example, the center of mass of MN activity in the lumbosacral levels generally shifted from rostral to caudal positions in two cycles for each step, revealing four major activation foci: two in the upper lumbar segments and two in the sacral segments. The results are consistent with the presence of at least two and possibly more pattern generators controlling the activation of lumbosacral MNs.

Action Potentials↗

PubMed2002

Complete laparoscopic ileal cystoplasty.

INTRODUCTION: Laparoscopic enterocystoplasty provides a minimally invasive approach to bladder augmentation in the patient with a neurogenic bladder. In previously published reports, portions of the procedure were performed extracorporeally. We report our technique of complete intracorporeal laparoscopic enterocystoplasty. TECHNICAL CONSIDERATIONS: Important elements of the operation include (a) preoperative evaluation of patient compliance and videourodynamic studies; (b) cystoscopic placement of externalized ureteral stents; (c) transperitoneal placement of five radially dilating trocars; (d) identification of the cecum; (e) proximal mobilization of ileum sufficient for pelvic placement; (f) measurement of ileal length with segment of precut vessel loop; (g) vertical cystotomy after incising peritoneum and entering the space of Retzius; (h) ileal division and side-to-side anastomosis using endoscopic gastrointestinal anastomosis staplers; (i) detubularization and freehand intracorporeal suturing into a U-shaped configuration; (j) fixing ileal patch at the 6 and 11-o'clock positions; (k) completion of ileal-bladder anastomosis in quadrants with running sutures; (l) irrigation of bladder and placement of a closed suction drain in the pelvis; and (m) cystogram 4 weeks postoperatively. CONCLUSIONS: Pure laparoscopic enterocystoplasty is an advanced procedure that is technically feasible and yields excellent results, but has unproven benefits. We perform the entire operation intracorporeally with traditional instruments and do not rely on suturing devices or extracorporeal knots. Additional experience and technological developments may result in routine laparoscopic urinary augmentation and continent diversion.

Anastomosis, Surgical↗

PubMed2005

Head stabilization on a continuously oscillating platform: the effect of a proprioceptive disturbance on the balancing strategy.

When standing and balancing on a continuously and predictably moving platform, body equilibrium relies on both anticipatory control and proprioceptive feedback. We have vibrated different postural muscles of the body to assess any effect of confounding the proprioceptive input on balance during such unstable conditions. Low and high platform oscillation frequencies were used, because different strategies are used to withstand the two perturbations. Eyes open (EO) and closed (EC) conditions were also tested, to assess whether the stabilizing effect of vision is independent from the proprioceptive disturbance. Subjects (n = 14) performed two series of trials, EO and EC: (1) quiet erect stance, (2) stance on the platform translating at 0.2 or 0.6 Hz sinusoidally in the anteroposterior (A-P) direction (dynamic conditions). Continuous bilateral vibration (90 Hz) was produced by two vibrators fixed to the following homonymous muscles: dorsal neck, quadriceps, biceps femoris, tibialis anterior, and triceps surae. Acquisition of body segments' displacement began 10 s after the start of platform translation. From markers fixed to head, hip, and malleolus, we computed the A-P oscillation of head and hip, body orientation in space, and cross-correlation (CC) and time-delay between malleolus and head trajectories. The results were (a) the head A-P oscillation was smaller with EO than EC, under both quiet stance and dynamic conditions; (b) vibration of tibialis and triceps surae, but not of other muscles, slightly increased head and body A-P oscillation with EC under dynamic conditions; (c) at 0.2 Hz but not at 0.6 Hz, for all visual and vibration conditions, there was a significant association between head and feet; (d) at 0.2 Hz, EC, neck muscle vibration increased this association, whereas vibration of the other muscles induced a major time delay in the oscillation of head compared with feet; (e) vibration of either neck or tibialis induced forward body leaning, while vibration of either triceps surae or biceps femoris induced backward leaning, with both EO and EC, under both static and dynamic conditions; (f) the head A-P oscillation, however, under dynamic conditions was not dependent on body leaning. The relatively scarce effects of proprioceptive disturbance on head stabilization and multijoint coordination (in spite of effects on body orientation similar to those observed during stance) speak for a major role of anticipatory control in the dynamic equilibrium task. However, the significant vibration-induced time delay in segments' coordination at low translation frequency, EC, suggests that the normally patterned Ia input promotes continuous adjustments of the feed-forward control mode.

Adaptation, Physiological↗

PubMed1984

Simultaneous temporal processing.

Seven experiments assessed the ability of rats to process temporal information from two internal clocks simultaneously and independently. In the first six experiments a light stimulus signalled an overall interval between the beginning of a trial and the availability of food reinforcement (e.g., a 50-s fixed interval). During the overall interval a sound stimulus was used to signal shorter intervals that divided the overall interval into equal segments. When there was a fixed temporal relation between the final segment signal and the availability of reinforcement, there was a double-scallop pattern of responding throughout the segmented overall interval; the function relating response rate to time during segment intervals was similar to the function relating response rate to time in unsegmented overall intervals; a change in response rate occurred at the time that a normally presented segment signal was omitted. Taken together, the results indicate that rats timed the overall interval and the segment intervals simultaneously and independently without interference. In Experiment 7 a light stimulus was used on some trials, and a sound stimulus was used on other trials to signal a discrete-trial 50-s peak procedure. When these two signals were presented in compound, there was a leftward shift of the response function, which suggests that rats timed both signals simultaneously. For all of the experiments a scalar timing model with specific stimulus integration rules is used to explain the results. The stimulus integration rule used in the first six experiments, in which there were two signals for the same reinforcement, was to respond if both the segment and the overall interval had exceeded a response threshold. The stimulus integration rule used in Experiment 7, in which there were two signals for different reinforcements, was to respond if the response threshold for either interval had been exceeded.

Animals↗

PubMed2006

Pattern of osteophytes and enthesophytes in the proximal ulna: an anatomic, paleopathologic, and radiologic study.

OBJECTIVE: To develop a schematic segmentation of the proximal ulna in order to detect, assess the frequency, and characterize the bony outgrowths arising from the trochlea and from the radial notch of the ulna, to enable differentiation of osteophytes from enthesophytes. MATERIALS AND METHODS: Eighty well-preserved ulna specimens from the collection of the San Diego Museum of Man were analyzed by two musculoskeletal radiologists. The trochlea and the radial notch of the ulna simulate the shape of a clock quadrant. The proximal ulna was divided into 24 anatomic areas. The relationships of the joint capsule and insertions of tendons and ligaments onto these area were assessed by the two readers, and the resulting appearances of bony outgrowths were compared at visual inspection and on Radiographs. RESULTS: The interobserver visual comparison was good in 17 areas out of 24, but poor correlation was found in 7 areas. In one case, difficulties in differentiating osteophytes originating from the brachialis muscle/ tendon (area 9) from an enthesophyte originating from the capsule insertion on the coronoid process (areas 2 or 3) occurredand between two different enthesophytes in a further case. Five cases had difficulties in defining differences in the grading system of the outgrowths. The percentage of outgrowths observed in each of the areas was globally high, especially in areas 9 and 10. On radiographs it was possible to observe irregularities in ten areas; in eight at a threshold of height of 2 mm (areas 1-4, 9, 10, 11, 14) and in two at a threshold of height of 3 mm (areas 5, 6). The two readers had the same difficulties in differentiating enthesophytes from osteophytes at radiographic and visual examination. CONCLUSION: Our segmentation scheme is reproducible and objective, and permitted the differentiation of the bony outgrowths arising from the proximal ulna into osteophytes and enthesophytes, which may be particularly useful for the in vivo assessment of abnormalities seen in elbow overuse syndromes.

Humans↗

PubMed2002

her1 and the notch pathway function within the oscillator mechanism that regulates zebrafish somitogenesis.

Somite formation is thought to be regulated by an unknown oscillator mechanism that causes the cells of the presomitic mesoderm to activate and then repress the transcription of specific genes in a cyclical fashion. These oscillations create stripes/waves of gene expression that repeatedly pass through the presomitic mesoderm in a posterior-to-anterior direction. In both the mouse and the zebrafish, it has been shown that the notch pathway is required to create the stripes/waves of gene expression. However, it is not clear if the notch pathway comprises part of the oscillator mechanism or if the notch pathway simply coordinates the activity of the oscillator among neighboring cells. In the zebrafish, oscillations in the expression of a hairy-related transcription factor, her1 and the notch ligand deltaC precede somite formation. Our study focuses on how the oscillations in the expression of these two genes is affected in the mutants aei/deltaD and des/notch1, in 'morpholino knockdowns' of deltaC and her1 and in double 'mutant' combinations. This analysis indicates that these oscillations in gene expression are created by a genetic circuit comprised of the notch pathway and the notch target gene her1. We also show that a later function of the notch pathway can create a segmental pattern even in the absence of prior oscillations in her1 and deltaC expression.

Animals↗

PubMed1984

The senescence of postmitotic mammalian cells: a cell-clock hypothesis.

A cell-clock hypothesis for the senescence of long-lived postmitotic cells is proposed, based on the concept that the cells cycle regularly between a synthetic and a degradative phase and that the synthetic phase of each cycle is initiated by transcription of a family or families of highly repetitive DNA. The initiator transcripts are conceived to activate other segments of DNA controlling the transcription of mRNAs. The basic senescence mechanism is postulated to be the uncorrected progressive conversion of 5-methylcytosine in repetitive DNA to thymine by hydrolytic deamination, causing an age-related decline in the number of active initiator transcripts and a progressive loss of cell vigor.

5-Methylcytosine↗

PubMed1995

Ciliary body neurilemoma. Unusual clinical findings intimating the diagnosis.

BACKGROUND: Neurilemomas (schwannomas) rarely occur intraocularly. When present, they pose a diagnostic dilemma for the physician and often are mistaken as a malignant lesion, resulting in enucleation. METHODS: The authors report the clinical findings of a 46-year-old man with a slowly progressive growing mass of the anterior chamber, associated with glaucoma and the development of cataract. To further delineate the tumor's features, ancillary techniques, including ultrasonography, computed tomography, and magnetic resonance imaging, were conducted. A definitive anterior chamber biopsy of the tumor was performed with histologic examination and electron microscopy. RESULTS: Ultrasonography, high-resolution computed tomography and magnetic resonance imaging showed a well-delineated mass of the inferior ciliary body involving nearly 5 clock hours of the angle. Two clinical features that suggested a longstanding tumor were brilliant transillumination of the mass (leading to the impression of a "cystic mass," not corroborated by ultrasonography) and retrodisplacement of the involved iris root. The histology, and particularly the electron microscopic features, confirmed the diagnosis of a neurilemoma, a benign tumor of the anterior segment. CONCLUSION: Intraocular neurilemomas are extremely rare tumors. Few are well documented with modern ancillary techniques. Clinical findings in conjunction with radiographic and ultrasonic features may support the diagnosis of a benign tumor. For this patient, confirmation via biopsy permitted combined cataract and glaucoma surgery to rehabilitate the eye, which retains 20/20 visual acuity 3 years after the procedure.

Anterior Chamber↗

PubMed1992

Gonioscopic changes in eyes with posterior chamber intraocular lenses.

The aim of this study is to determine the effects of posterior chamber implantation on angle structures. First, without previous knowledge of the position of lens haptics, 360 degrees gonioscopy was performed and any changes in the angle structures were recorded. Then, the pupil was dilated to determine the exact position of the intraocular lens haptics. The apposition of peripheral iris to angle structures or, at least, the narrowing of the angle corresponding to the lens haptic position was observed in almost all of the 117 examined eyes, with no difference found between bag and sulcus implantation. Peripheral anterior synechia overlying the lens haptic was observed in 49 (41.8%) of 117 eyes. Interestingly, we also noted that there was marked and well-limited clumping of pigment in the angle at 6 o'clock position in 67 (57.2%) of 117 eyes. In conclusion, we feel that posterior chamber intraocular lenses are not completely innocuous to the angle structures.

Adult↗

PubMed2004

Scleral and corneal laceration with iris prolapse caused by an eagle claw.

BACKGROUND: To describe the visual rehabilitation after surgical treatment of an ocular injury sustained during an attack by a bird of prey. METHODS: A 51-year-old woman who was attacked by an eagle in a cage had a laceration of cornea and sclera at 9 o' clock, an iris prolapse that was jammed into the scleral wound, and a flat anterior chamber with hyphema. The uncorrected visual acuity was hand movements. Surgical treatment was performed immediately and included iris repositioning and suturing, scleral and conjunctival suturing, and transscleral cryotherapy to the retina. RESULTS: Eight months later, the best corrected visual acuity was 20/20. The anterior segment showed a posterior synechia in the area of the iris repair and an almost round pupil; the crystalline lens showed only a localized opacification. CONCLUSIONS: A bird of prey, even though caged, can injure an eye in humans. With immediate surgical treatment, good visual rehabilitation was achieved in this case. It should be reiterated that spectacles offer no protection against ocular trauma in these cases.

Animals↗

PubMed2002

Phase shifting the hamster circadian clock by 15-minute dark pulses.

The mammalian circadian pacemaker can be phase shifted by exposure to a period of darkness interrupting otherwise continuous light. Circadian phase shifting by dark pulses was interpreted originally as reflecting a photic mirror-image mechanism, but more recent observations suggest that dark pulse-induced phase shifting may be mediated by a nonphotic, behavioral state-dependent mechanism. The authors recently presented evidence indicating that the dark-pulse phase response curve (PRC) is in fact a complex function, reflecting both photic mirror image and nonphotic mechanisms at different phases of the circadian cycle. Previous studies of dark pulse-induced phase shifting have universally employed relatively long (2 to 6 h) pulses, which complicates PRC analysis due to the extended segment of the underlying PRC spanned by such a long pulse. The present study was therefore designed to examine the phase-shifting effects of brief 15-min dark pulses presented at both mid-subjective day and subjective dusk, and to explore the possible activity dependence of these effects by using physical restraint to prevent evoked locomotor activity. The results indicate that 15-min dark pulses are effective phase-shifting stimuli at both midday and dusk. Furthermore, as with longer dark pulses, phase shifting by 15-min dark pulses is completely blocked by physical restraint during subjective day but combines in a simple additive manner with the independent phase-shifting effect of restraint at subjective dusk.

Animals↗

PubMed1990

'Compensatory slippage' in the evolution of ribosomal RNA genes.

The distribution patterns of shared short repetitive motifs in the expansion segments of the large subunit rRNA genes of different species show that these segments are coevolving as a set and that in two examined vertebrate species the RNA secondary structures are conserved as a consequence of runs of motifs in one region being compensated by complementary motifs in another. These unusual processes, involving replication-slippage, have implications for the evolution of ribosomal RNA and for the use of the rDNA multigene family as a 'molecular clock' for assessing relationships between species.

Animals↗

PubMedDate not supplied

Macular hole following conventional repair of bullous retinal detachment using air injection (D-ACE procedure).

PURPOSE: Sequential drainage of subretinal fluid (D), injection of air (A), cryotherapy (C), and application of local explants (E) (D-ACE) sequence was introduced in order to overcome the problems encountered in managing superior bullous detachments from multiple large equatorial breaks. The authors recently observed the occurrence of a full-thickness macular hole in one patient developing the day after he underwent a D-ACE procedure. METHODS: A 61-year-old man presented a bullous retinal detachment in the right eye extending from the 9:30 to the 2 o'clock position, and posteriorly to the vascular arcades two retinal tears were noted, at the equator at 11 o'clock, and anterior to the equator at 12 o'clock. The patient underwent a D-ACE procedure. Subretinal fluid was drained above the lateral rectus muscle at the equator. One and a half milliliters of air were injected 3.5 mm from the limbus midway between the superior and the medial rectus insertions. Cryotherapy was applied to the retinal breaks. A 240 encircling band was used in conjunction with a 276 tyre segment at the level of the tears. RESULTS: One day after surgery, the retina was flat, but a full-thickness macular hole could be seen with a surrounding cuff of subretinal fluid. CONCLUSIONS: The mechanisms proposed to explain the occurrence of full-thickness macular holes after D-ACE may involve the concurrence of scleral elongation and vitreofoveal traction by means of previous partial posterior vitreous detachment with persistent posterior attachments at the fovea.

Air↗

PubMed2001

Clinical variations and complications of Coats disease in 150 cases: the 2000 Sanford Gifford Memorial Lecture.

PURPOSE: The purpose of this report is to review the clinical variations and natural course of Coats disease, using strict diagnostic guidelines. METHODS: In a retrospective, consecutive series, Coats disease was defined as idiopathic retinal telangiectasia with intraretinal or subretinal exudation without appreciable signs of retinal or vitreal traction. We reviewed our experience with the clinical features, complications, and diagnostic approaches to Coats disease. RESULTS: In 150 consecutive patients (158 eyes), Coats disease was diagnosed at a median age of 5 years (range, 1 month to 63 years), occurred in 114 males (76%), and was unilateral in 142 patients (95%). There was no predilection for race or laterality. The most common referral diagnoses were Coats disease in 64 cases (41%) and retinoblastoma in 43 (27%). The first symptom or sign was decreased visual acuity in 68 cases (34%), strabismus in 37 (23%), leukocoria in 31 (20%), and 13 patients (8%) were asymptomatic. Visual acuity at presentation was 20/200 to no light perception in 121 eyes (76%). The anterior segment was normal in 142 eyes (90%). The retinal telangiectasia involved the midperipheral or peripheral fundus in 156 of the 158 eyes (99%) and was restricted to the macular area in two eyes (1%); involved mainly the temporal fundus in 66 eyes (42%), inferior fundus in 41 eyes (26%), and more than one sector in 34 eyes (22%). Retinal exudation was present in all 12 clock hours in 86 eyes (55%) and six or more clock hours in 115 eyes (73%). There was a total retinal detachment in 74 eyes (47%) and neovascular glaucoma in 12 (8%). Retinal macrocysts were present in 18 eyes (11%), a vasoproliferative tumor in nine eyes (6%) and retinal neovascularization in four eyes (3%). Fluorescein angiography in 49 of the 158 eyes (37%) disclosed early hyperfluorescence of the telangiectasias and macular edema in 18 of eyes (37%). Ultrasonography typically showed a retinal detachment but no solid mass. CONCLUSIONS: Coats disease is a distinct clinical entity characterized by idiopathic retinal telangiectasia and retinal exudation. It is usually unilateral, occurs mostly in young males, and can cause severe visual loss resulting from exudative retinal detachment. The clinician should follow strict criteria in making the diagnosis, to avoid confusing Coats disease with other forms of exudative retinopathy.

Adolescent↗

PubMed2002

Prevalence of coronary occlusion and outcome of an immediate invasive strategy in suspected acute myocardial infarction with and without ST-segment elevation.

The prevalence of flow-limiting coronary lesions at the time of presentation in patients with non-ST-segment elevation myocardial infarction (NSTEMI) is unknown. Because rational reperfusion strategies depend on early, accurate identification of coronary flow limitation, we performed coronary angiography at the time of presentation of patients with suspected NSTEMI. We also evaluated outcomes of an immediate interventional strategy. A comparison is made with suspected ST-segment elevation myocardial infarction (STEMI). Unselected consecutive patients with suspected STEMI or NSTEMI were enrolled in a prospective observational cohort study. Suspected STEMI was defined according to standard criteria. Suspected NSTEMI was identified by clinical evaluation of symptoms, electrocardiographic changes, persistence of ischemic pain for >20 minutes despite treatment, and/or hemodynamic instability. Biochemical evidence of myocardial necrosis on presentation was not mandatory. An immediate, around-the-clock invasive strategy was applied. Significant coronary lesions were found in 94% of 279 patients with suspected STEMI and in 90% of 125 patients with suspected NSTEMI, and coronary occlusion or flow limitation was present in 75% and 63% of patients, respectively. Immediate percutaneous coronary intervention was performed in 74% and 60%, respectively, and an additional 13% and 18%, respectively, had coronary artery bypass surgery during the index admission. In-hospital mortalities in the patients with suspected STEMI and NSTEMI were 4.7% and 5.6%, respectively. An additional 1.9% and 2.5% died at 6 months. The prevalence of coronary flow limitation in clinically suspected NSTEMI is almost as high as in suspected STEMI. Short- and long-term outcomes of an immediate invasive strategy are similar for the 2 conditions.

Adult↗

PubMed2002

Melanopsin-containing retinal ganglion cells: architecture, projections, and intrinsic photosensitivity.

The primary circadian pacemaker, in the suprachiasmatic nucleus (SCN) of the mammalian brain, is photoentrained by light signals from the eyes through the retinohypothalamic tract. Retinal rod and cone cells are not required for photoentrainment. Recent evidence suggests that the entraining photoreceptors are retinal ganglion cells (RGCs) that project to the SCN. The visual pigment for this photoreceptor may be melanopsin, an opsin-like protein whose coding messenger RNA is found in a subset of mammalian RGCs. By cloning rat melanopsin and generating specific antibodies, we show that melanopsin is present in cell bodies, dendrites, and proximal axonal segments of a subset of rat RGCs. In mice heterozygous for tau-lacZ targeted to the melanopsin gene locus, beta-galactosidase-positive RGC axons projected to the SCN and other brain nuclei involved in circadian photoentrainment or the pupillary light reflex. Rat RGCs that exhibited intrinsic photosensitivity invariably expressed melanopsin. Hence, melanopsin is most likely the visual pigment of phototransducing RGCs that set the circadian clock and initiate other non-image-forming visual functions.

Amino Acid Sequence↗