diff --git a/.gitignore b/.gitignore
index 35d62ca..fa2a08d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,6 @@
 .DS_Store
 ._*
 tmp/
-/.ipynb_checkpoints/
+.ipynb_checkpoints/
 *.pyc
 data/pubmed/*.xml

diff --git a/.gitignore b/.gitignore
index 35d62ca..fa2a08d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,6 @@
 .DS_Store
 ._*
 tmp/
-/.ipynb_checkpoints/
+.ipynb_checkpoints/
 *.pyc
 data/pubmed/*.xml
diff --git a/py/.ipynb_checkpoints/pandas-checkpoint.ipynb b/py/.ipynb_checkpoints/pandas-checkpoint.ipynb
deleted file mode 100644
index af29373..0000000
--- a/py/.ipynb_checkpoints/pandas-checkpoint.ipynb
+++ /dev/null
@@ -1,108 +0,0 @@
-{
- "cells": [
-  {
-   "cell_type": "code",
-   "execution_count": 4,
-   "metadata": {
-    "collapsed": true,
-    "pycharm": {
-     "is_executing": false,
-     "name": "#%%\n"
-    }
-   },
-   "outputs": [],
-   "source": [
-    "import numpy as np\n",
-    "\n",
-    "np.random.seed(123)\n",
-    "coins = []\n",
-    "coins_random_walk = [0]\n",
-    "for i in range(10):\n",
-    "    if np.random.randint(0,2) == 0:\n",
-    "        coins_random_walk.append(0)\n",
-    "        coins.append(\"head\")\n",
-    "    else:\n",
-    "        coins.append(\"tail\")\n",
-    "print(coins)"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 1,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "A = [1,2,3]\n",
-    "B = A + [4,5]\n",
-    "B.append(6)\n"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 6,
-   "metadata": {
-    "collapsed": false,
-    "pycharm": {
-     "is_executing": false,
-     "name": "#%% \n"
-    }
-   },
-   "outputs": [],
-   "source": [
-    "# matplotlib\n",
-    "import matplotlib.pyplot as plt\n",
-    "plt.scatter([1,2,3], [7,8,9], s=[3,60,90], c=['red','blue','green'], alpha=0.5)\n",
-    "\n",
-    "plt.text(10, 8.5, \"Here is some\")\n",
-    "\n",
-    "plt.grid(True)\n",
-    "\n",
-    "plt.xscale('log') \n",
-    "plt.xlabel(\"X Label\")\n",
-    "plt.ylabel(\"Y Label\")\n",
-    "plt.title(\"Title\")\n",
-    "plt.xticks([10,20,30], [\"10x\", \"20x\",\"30x\"])\n",
-    "plt.show()"
-   ]
-  }
- ],
- "metadata": {
-  "authors": [],
-  "description": "",
-  "kernelspec": {
-   "display_name": "Python 3",
-   "language": "python",
-   "name": "python3"
-  },
-  "language_info": {
-   "codemirror_mode": {
-    "name": "ipython",
-    "version": 3
-   },
-   "file_extension": ".py",
-   "mimetype": "text/x-python",
-   "name": "python",
-   "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython3",
-   "version": "3.7.3"
-  },
-  "nteract": {
-   "version": "nteract-on-jupyter@2.1.3"
-  },
-  "pycharm": {
-   "stem_cell": {
-    "cell_type": "raw",
-    "metadata": {
-     "collapsed": false
-    },
-    "source": [
-     "Simulate \n"
-    ]
-   }
-  },
-  "tags": [],
-  "title": "Pandas Playground"
- },
- "nbformat": 4,
- "nbformat_minor": 0
-}