\documentclass{ukart}
\setcounter{errorcontextlines}{999}
\makeatletter
%
% Twee, in its wisdom, has a redefined LaTeX logo
%
%\DeclareRobustCommand{\LaTeX}{L\kern-.36em
%        {\setbox0\hbox{T}%
%         \vbox to\ht0{\hbox{$\m@th$%
%                            \csname S@\f@size\endcsname
%                            \fontsize\sf@size\z@
%                            \math@fontsfalse\selectfont
%                            A}%
%                      \vss}%
%        }%
%        \kern-.15em
%        \TeX}
%
% which sets the A in scripstyle jammed up to the top of the T; it
% also has the advantage that it's set in the same font as the
% surrounding text.  However, the esteemed bbeeton says the logo looks
% "squidge awful" in italic text (I agree; and the same is true of its
% behaviour in slanted text)
%
% So here's a version that allows for the italic slant of the leading L
\DeclareRobustCommand{\latex}{L%
        {\setbox0\hbox{T}%
         \setbox\@tempboxa\hbox{$\m@th$%
                                \csname S@\f@size\endcsname
                                \fontsize\sf@size\z@
                                \math@fontsfalse\selectfont
                                A}%
         \@tempdima\ht0
         \advance\@tempdima-\ht\@tempboxa
         \@tempdima\strip@pt\fontdimen1\font\@tempdima
         \advance\@tempdima-.36em
         \kern\@tempdima
         \vbox to\ht0{\box\@tempboxa
                      \vss}%
        }%
        \kern-.15em
        \TeX}
%
% of course, we could modify this not to do all those awful sums when
% the font isn't slanted, but (perhaps) this isn't today's
% problem\dots
%
% Now for a few demonstrations of the effect achieved
\begin{document}
Demo with the modification of the current \LaTeX{} logo

\begin{center}
\LARGE\begin{tabular}{l|ccc}
&\normalsize\sf roman&\normalsize\sf italic&\normalsize\sf slanted\\
\hline
\normalsize\sf old & \LaTeX & \textit{\LaTeX} & \textsl{\LaTeX} \\
\normalsize\sf new & \latex & \textit{\latex} & \textsl{\latex} \\
\end{tabular}
\end{center}
%
% Here's something that does it with the `original' (Lamport's)
% definition.
%
% (In fact this is a bit of a cheat, since the last 2.09 had
% \reset@font\rm at the start, and of course, it got defined as a
% protected command in the LaTeX 2.09 fashion, but what the hell, eh?)
\def\LaTeX{L\kern-.36em\raise.3ex\hbox{\textsc{a}}\kern-.15em\TeX}%
\def\latex{\@tempdima.3ex
           \@tempdima\strip@pt\fontdimen1\font\@tempdima
           \advance\@tempdima-0.36em\relax
           L\kern\@tempdima\raise.3ex\hbox{\textsc{a}}\kern-.15em\TeX}%
%
% and a demo of that
\par\noindent Demo with the modification of the original \LaTeX{} logo

\begin{center}
\LARGE\begin{tabular}{l|ccc}
&\normalsize\sf roman&\normalsize\sf italic&\normalsize\sf slanted\\
\hline
\normalsize\sf old & \LaTeX & \textit{\LaTeX} & \textsl{\LaTeX} \\
\normalsize\sf new & \latex & \textit{\latex} & \textsl{\latex} \\
\end{tabular}
\end{center}
\end{document}