Graph (JS + data) that belongs to http://graus.nu/blog/force-directed-graphs-playing-around-with-d3-js/

d3.js graph

var graph = 'graph.json'

	var w = 960,
	h = 700,
	r = 10;

var vis = d3.select(".graph")
	.append("svg:svg")
	.attr("width", w)
	.attr("height", h)
	.attr("pointer-events", "all")
	.append('svg:g')
	.call(d3.behavior.zoom().on("zoom", redraw))
	.append('svg:g');

vis.append('svg:rect')
    .attr('width', w)
    .attr('height', h)
    .attr('fill', 'rgba(1,1,1,0)')

function redraw() {
	console.log("here", d3.event.translate, d3.event.scale);
	vis.attr("transform","translate(" + d3.event.translate + ")" + " scale(" + d3.event.scale + ")"); }	
	
	var force = d3.layout.force()
		.gravity(.05)
		.charge(-200)
		.linkDistance( 60 )
		.size([w, h]);
	
	var svg = d3.select(".text").append("svg")
		.attr("width", w)
		.attr("height", h);
		
d3.json(graph, function(json) {
		var link = vis.selectAll("line")
			.data(json.links)
			.enter().append("line")
			.attr("stroke-opacity", function(d) { if(d.label == 'is a') { return '0.8';} else{ return '0.2'; }; })
			.attr("stroke-width","6")
			.style("stroke", function(d) { if(d.color !== null) { return d.color;}; })
			.on("mouseover", function(){d3.select(this).style("stroke", "#999999").attr("stroke-opacity", "1.0");})
			.on("mouseout", function(){d3.select(this).style("stroke", function(d) { if(d.color !== null) { return d.color;}; }).attr("stroke-opacity", function(d) { if(d.label == 'is a') { return '0.8';} else { return '0.2'; };}) });

			link.append("title")
				.text(function(d) { return d.label } );			

		var node = vis.selectAll("g.node")
			.data(json.nodes)
			.enter().append("svg:g")
			.attr("class","node")
			.call(force.drag);
			
			node.append("svg:circle")
				.attr("r", function(d) {
				if (d.size > 0) 
				{ return 10+(d.size*2); } 
				else
				{ return 10; }} )
				.style("fill", function(d) { if(d.style == 'filled') { return d.color;}; })
				.style("stroke", function(d) { if(d.style !== 'filled') { return d.color;}; })
				.style("stroke-width", "4")
				.on("mouseover", function(){d3.select(this).style("fill", "#999");})
				.on("mouseout", function(d) {
					if (d.style == 'filled') { d3.select(this).style("fill",d.color); }
					else {
					d3.select(this).style("stroke",d.color);
					d3.select(this).style("fill","black");
					} } );
				
			node.append("svg:text")
				.attr("text-anchor", "middle") 
				.attr("fill","white")
				.style("pointer-events", "none")
				.attr("font-size", function(d) { if (d.color == '#b94431') { return 10+(d.size*2) + 'px'; } else { return "9px"; } } )
				.attr("font-weight", function(d) { if (d.color == '#b94431') { return "bold"; } else { return "100"; } } )
				.text( function(d) { if (d.color == '#b94431') { return d.id + ' (' + d.size + ')';} else { return d.id;} } ) ;
				
			node.append("title")
				.text(function(d) { return d.URI } );

		force
			.nodes(json.nodes)
			.links(json.links)
			.on("tick", tick)
			.start();
			
  function tick() {
    node.attr("cx", function(d) { return d.x; })
        .attr("cy", function(d) { return d.y; })
		.attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")";});

    link.attr("x1", function(d) { return d.source.x; })
        .attr("y1", function(d) { return d.source.y; })
        .attr("x2", function(d) { return d.target.x; })
        .attr("y2", function(d) { return d.target.y; });
  }
});

graph.json

{
  "directed": true,
  "graph": [],
  "nodes": [
    {
      "color": "#da991c",
      "id": "Brain Part"
    },
    {
      "color": "#b94431",
      "size": 9,
      "id": "Corpus Callosum",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Corpus_Callosum"
    },
    {
      "color": "#333333",
      "id": "Diagnostic Procedure"
    },
    {
      "color": "#b94431",
      "size": 6,
      "id": "Cerebral Fornix",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Cerebral_Fornix"
    },
    {
      "id": "Cerebral Hemisphere"
    },
    {
      "id": "Cerebral Gyrus"
    },
    {
      "color": "#b94431",
      "size": 7,
      "id": "Magnetic Resonance Imaging",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Magnetic_Resonance_Imaging"
    },
    {
      "color": "#b94431",
      "size": 6,
      "id": "Thalamus",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Thalamus"
    },
    {
      "color": "#333333",
      "id": "Imaging Technique"
    },
    {
      "color": "#b94431",
      "size": 3,
      "id": "Sagittal Plane",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Sagittal_Plane"
    },
    {
      "color": "#333333",
      "id": "Plane"
    },
    {
      "color": "#b94431",
      "size": 6,
      "id": "White Matter",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#White_Matter"
    },
    {
      "color": "#333333",
      "id": "Nerve Tissue and Nerve Sheaths"
    },
    {
      "id": "Brain White Matter"
    },
    {
      "id": "Brain Ventricle"
    },
    {
      "id": "Technique"
    },
    {
      "id": "Physical Chemical Technique"
    },
    {
      "id": "Diagnostic Imaging"
    },
    {
      "id": "Organ"
    },
    {
      "color": "#333333",
      "id": "Splenium of the Corpus Callosum"
    },
    {
      "color": "#333333",
      "id": "Central Nervous System Part"
    },
    {
      "color": "#333333",
      "id": "Clinical or Research Activity"
    },
    {
      "color": "#333333",
      "id": "Cerebral White Matter"
    },
    {
      "color": "#333333",
      "id": "Nerve Tissue, Neuroepithelial Tissue, and Nerve Sheaths"
    },
    {
      "id": "Thing"
    },
    {
      "id": "Infratentorial Brain"
    },
    {
      "id": "Spectroscopy"
    },
    {
      "id": "Forebrain"
    },
    {
      "id": "Thalamencephalon"
    },
    {
      "color": "#da991c",
      "id": "Anatomic Structure, System, or Substance"
    },
    {
      "color": "#da991c",
      "id": "Nerve Tissue"
    },
    {
      "id": "Activity"
    },
    {
      "color": "#333333",
      "id": "Nervous System Part"
    },
    {
      "color": "#333333",
      "id": "Cerebral Cortex"
    },
    {
      "color": "#333333",
      "id": "Intervention or Procedure"
    },
    {
      "id": "Brain"
    },
    {
      "color": "#333333",
      "id": "Body Part"
    },
    {
      "color": "#333333",
      "id": "Tissue"
    },
    {
      "color": "#b94431",
      "size": 7,
      "id": "Lateral Ventricle",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Lateral_Ventricle"
    },
    {
      "color": "#b94431",
      "size": 7,
      "id": "Cingulate Gyrus",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Cingulate_Gyrus"
    },
    {
      "color": "#b94431",
      "size": 6,
      "id": "Mamillary Body",
      "URI": "http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#Mamillary_Body"
    },
    {
      "color": "#333333",
      "id": "Conceptual Entity"
    },
    {
      "color": "#333333",
      "id": "Occipital Horn of the Lateral Ventricle"
    },
    {
      "id": "Research Technique"
    }
  ],
  "links": [
    {
      "source": 0,
      "target": 20
    },
    {
      "color": "#b94431",
      "source": 1,
      "target": 4
    },
    {
      "color": "#b94431",
      "source": 1,
      "target": 22
    },
    {
      "source": 2,
      "target": 34
    },
    {
      "color": "#b94431",
      "source": 3,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 3,
      "target": 4
    },
    {
      "color": "#b94431",
      "source": 4,
      "target": 27
    },
    {
      "color": "#b94431",
      "source": 5,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 5,
      "target": 33
    },
    {
      "color": "#b94431",
      "source": 6,
      "target": 17
    },
    {
      "color": "#b94431",
      "source": 7,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 7,
      "target": 28
    },
    {
      "source": 8,
      "target": 2
    },
    {
      "color": "#b94431",
      "source": 9,
      "target": 10
    },
    {
      "color": "#b94431",
      "source": 10,
      "target": 41
    },
    {
      "source": 11,
      "target": 30
    },
    {
      "source": 12,
      "target": 23
    },
    {
      "color": "#b94431",
      "source": 13,
      "target": 35
    },
    {
      "color": "#b94431",
      "source": 13,
      "target": 11
    },
    {
      "color": "#b94431",
      "source": 13,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 14,
      "target": 35
    },
    {
      "source": 14,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 15,
      "target": 31
    },
    {
      "color": "#b94431",
      "source": 16,
      "target": 43
    },
    {
      "source": 17,
      "target": 8
    },
    {
      "color": "#b94431",
      "source": 18,
      "target": 29
    },
    {
      "color": "#b94431",
      "source": 19,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 19,
      "target": 1
    },
    {
      "source": 20,
      "target": 32
    },
    {
      "source": 21,
      "target": 31
    },
    {
      "color": "#b94431",
      "source": 22,
      "target": 13
    },
    {
      "source": 23,
      "target": 37
    },
    {
      "color": "#b94431",
      "source": 25,
      "target": 35
    },
    {
      "color": "#b94431",
      "source": 25,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 26,
      "target": 16
    },
    {
      "color": "#b94431",
      "source": 26,
      "target": 17
    },
    {
      "color": "#b94431",
      "source": 27,
      "target": 35
    },
    {
      "color": "#b94431",
      "source": 28,
      "target": 35
    },
    {
      "source": 29,
      "target": 24
    },
    {
      "source": 30,
      "target": 12
    },
    {
      "source": 31,
      "target": 24
    },
    {
      "source": 32,
      "target": 36
    },
    {
      "color": "#b94431",
      "source": 33,
      "target": 4
    },
    {
      "source": 34,
      "target": 21
    },
    {
      "color": "#b94431",
      "source": 35,
      "target": 18
    },
    {
      "source": 36,
      "target": 29
    },
    {
      "source": 37,
      "target": 29
    },
    {
      "color": "#b94431",
      "source": 38,
      "target": 4
    },
    {
      "color": "#b94431",
      "source": 38,
      "target": 14
    },
    {
      "color": "#b94431",
      "source": 39,
      "target": 5
    },
    {
      "color": "#b94431",
      "source": 40,
      "target": 0
    },
    {
      "source": 41,
      "target": 24
    },
    {
      "color": "#b94431",
      "source": 42,
      "target": 0
    },
    {
      "color": "#b94431",
      "source": 42,
      "target": 38
    },
    {
      "color": "#b94431",
      "source": 43,
      "target": 15
    }
  ],
  "multigraph": false
}

I tried it but mouseover and click options are not working it is static not dynamic as example. What can be problem?