How to makehelical wheeldiagram

The Heckler & Koch HK416 is equipped with a proprietary accessory rail handguard with MIL-STD-1913 rails on all four sides, used here to mount a vertical foregrip and Aimpoint CompM4 red dot sight

By default: nonpolar residues (e.g. glycine, tryptophan) will be colored grey; polar residues (e.g. serine, threonine) will be colored yellow; acidic residues with a negative charge at physiologic pH (e.g. aspartic acid, glutamic acid) will be colored red; and basic residues with a positive charge at physiologic pH (e.g. lysine, arginine) will be colored blue. This color scheme can be modified using the col parameter, which accepts a character vector with 4 elements, each of which must be an element of grDevices::colors(). The one-letter code for each residue can also be overlaid on each residue by setting the labels parameter to TRUE.

The rail itself dates from work by the A.R.M.S. company in the early 1980s and Otto Repa in standardizing the Weaver design.[citation needed] Specifications for the M16A2E4 rifle and the M4E1 carbine received type classification generic in December 1994.[citation needed] These were the M16A2[1] and the M4[2] modified with new upper receivers where rails replaced hand guards.

Helical wheel generatoronline

The following code loads the helixvis package and the sample data that comes with it - these will be used later in this vignette.

Helical wheels provide a bird's eye view of an \(\alpha\)-helical peptides and are particularly helpful at highlighting prominent hydrophobic faces to explain a large hydrophobic moment [@eisenberg1982; @dathe1997] and design antimicrobial peptides [@chen2005; @jiang2011].

Wenxiang diagrams are quite similar to helical wheels, with the exception that distance from the first residue is denoted by distance from the center of the spiral. Thus, wenxiang diagrams visually provide the order of amino acids in the sequence. The code used to generate wenxiang diagrams is analogous to that for generation of helical wheels.

Helical wheel generatorfree

The helixvis R package allows users to construct 2-dimensional visualizations of 3-dimensional \(\alpha\)-helical oligopeptides in a programmatic, reproducible manner. Currently, helixvis implements visualization of helical wheels, introduced by @wheeldiag, and wenxiang diagrams, introduced by @wenxiangdiag.

The Picatinny rail (/ˈpɪkətɪni/ or /ˌpɪkəˈtɪni/), also known as a MIL-STD-1913 rail, STANAG 2324 rail, or tactical rail, is a bracket on some firearms that provides a standard mounting platform for accessories and attachments, similar to the Weaver rail mount.

The rail consists of a series of ridges with a T-shaped cross-section interspersed with flat "spacing slots." Accessories are mounted either by sliding them on from one end or the other; by means of a Weaver mount which is clamped to the rail with bolts, thumbscrews or levers; or onto the slots between the raised sections.

The following code blocks and figures reproduce the figures from the Helical Wheel section, redrawn as wenxiang diagrams.

Helical wheel generatoronline free

The Picatinny rail was originally for mounting scopes atop the receivers of larger caliber rifles, but, once established, its use so expanded to other such accessories as tactical lights, laser aiming modules, night vision devices, reflex sights, foregrips, bipods, and bayonets that Picatinny rails and accessories have replaced iron sights in the design of many firearms, and they are also on the undersides of semi-automatic pistol frames and grips. Their usefulness has led to their being used even in paintball and airsoft.

The rail is named after the Picatinny Arsenal in New Jersey. The Picatinny Arsenal's role with the rail was to test/evaluate it and to create a military standard for it. This was Mil-STD-1913, dated 3 February 1995.[3]

A prototypical \(\alpha\)-helix has approximately 3.6 residues per turn [@helixorig], implying a 100\(^\text{o}\) rotation between consecutive residues. After 18 rotations, the 19th residue returns to the same angle as the 1st residue. Since helical wheels place all residues at an equal radius away from the center, having the same angle of rotation would cause complete overlap of the 1st and 19th residues. As such, helical wheels are limited to plotting 18 residues in a single turn, although some tools do allow for plotting of more than 1 turn [@heliquest]. For consistency, we also limit wenxiang diagrams to 18 residues.

The Picatinny locking slot width is 0.206 in (5.23 mm). The spacing of slot centers is 0.394 in (10.01 mm) and the slot depth is 0.118 in (3.00 mm).[4] The only differences between the Picatinny rail and the similar Weaver rail are the size of these slots and the fact that they are standardized. Weaver rails have a slot width of 0.180 in (4.57 mm), but are not necessarily consistent in the spacing of slot centers.[5] Some accessories are designed to fit on both Weaver and Picatinny rails; but most Picatinny devices will not fit on Weaver rails.[5] As of May 2012, however, most mounting rails are cut to Picatinny standards, and many accessories come with the recoil pin cut to the Weaver-compatible diameter. Also, many rail-mounted accessories come with only a single recoil pin – avoiding the issue of differing slot spacing.