！implicit_figures中的错误：参数类型无效

Question

今天早上更新R studio之后，我的R markdown文件似乎不再起作用，一旦尝试编织为PDF，就会出现以下错误：

Error in !implicit_figures : invalid argument type
Calls: <Anonymous> ... <Anonymous> -> output_format -> pandoc_options-> from_rmarkdown
Execution halted

我的YAML标头看起来像这样：

 ---
 title: "Surveillance Report"
fontsize: 12pt
header-includes:
- \usepackage{setspace}
- \usepackage{fancyhdr}
- \usepackage{url}
- \usepackage{lmodern}
- \usepackage[T1]{fontenc}
- \usepackage{helvet}
- \usepackage{eso-pic,graphicx,transparent}
output:
  pdf_document:
    fig_caption: yes8.40  
    includes:
      in_header: PHA_TEST2.tex
bibliography: bibliography.bib
csl: bmj.csl
---
\AddToShipoutPictureBG*{
\put(0,0){%
\parbox[b][\paperheight]{\paperwidth}{%
\centering{\transparent{0.2} \includegraphics[width=\paperwidth,     height=\paperheight]{plates2017_lp2.jpg}}%
    }
  }
}
\onehalfspacing
\addtolength{\headheight}{1.0cm}
\pagestyle{fancyplain}
\pagenumbering{gobble} 
\lhead{\includegraphics[height=1.2cm]{PHAlogo.png}}
\newpage
\pagenumbering{arabic} 
\setcounter{tocdepth}{3}
\tableofcontents
\renewcommand{\familydefault}{\sfdefault}

有人可以帮忙吗？