13th Community Wide Experiment on the
Critical Assessment of Techniques for Protein Structure Prediction
Improvements in models over copying from templates. Target: T0996
Results Home Table Browser Estimate of Model Accuracy Results RR Assessment Results
  Tables   GDT Plots   Local Accuracy   Position-specific alignment   Templates   Help
 
Selected templates/models  |  Models strip charts  |  Templates strip charts
Models / 25 Best templates vs targets CA-CA distances
View: Templates Model Difference     
Green line: distance between the aligned CA atoms in a template and the experimental structure in the LGA sequence-independent superposition under the 5A distance cutoff (see LGA description).
Blue line: distance between the corresponding CA atoms in a model and the experimental structure in the LGA sequence-independent superposition under the 5A distance cutoff.
Red line = (blue line) - (green thick line): difference between the corresponding Model-Target and Template-Target CA-CA distances (see above). Negative values show regions where a model has better fit to the target than the template, i.e. areas of potential improvement over the template.
Thin lines: other templates
The plot above is generated applying the moving average method with window of 3 positions.
Color gamma <-5 (-5; -2) (-2; -0.5) (-0.5; 0.5) (0.5; 2) (2; 5) >5 or N/A
Differences percentage0.0%20.6%11.2%46.0%6.1%16.1%0.0%
Radio buttons select the template for which difference is calculated

Checkboxes select template for visualization in the graph

* the best template selected by assessors

Top 25 Templates
  #TemplatesLGA_SRMSD
1 5uvnE 18.843 2.41
2 5uw8F 10.701 1.62
3 5uw2C 10.497 1.56
4 1pj5A 7.135 2.33
5 1nkkA 6.882 1.89
6 5mznA 6.824 2.17
7 1njuA 6.814 2.04
8 1id4A 6.767 2.03
9 1pkyA 6.706 2.43
10 5tl4B 6.694 2.44
11 1pj6A 6.692 2.27
12 3ad7A 6.672 2.21
13 5x1mA 6.66 2.32
14 4pabB 6.656 2.63
15 1layA 6.654 1.97
16 1njtD 6.639 1.98
17 1a5uB 6.63 2.64
18 5x1kA 6.621 2.41
19 1nrkA 6.617 2.35
20 1iegA 6.583 1.83
21 1vlyA 6.565 2.36
22 4v07A 6.541 2.1
23 1at3A 6.536 2.04
24 1e0tC 6.532 2.49
25 2gagA 6.51 2.23
Models
 #NameLGA_SRMSDGDT_TS 
1 T0996TS366_1 29.632 2.26 36.90
2 T0996TS366_2 30.696 2.33 36.21
3 T0996TS192_1 24.349 2.73 30.83
4 T0996TS068_3 23.355 2.74 28.12
5 T0996TS068_1 23.896 2.67 28.00
6 T0996TS068_2 23.633 2.67 27.89
7 T0996TS068_5 23.571 2.71 27.89
8 T0996TS068_4 23.593 2.70 27.89
9 T0996TS344_3 22.584 2.66 26.32
10 T0996TS322_2 21.63 2.61 26.02
11 T0996TS322_1 19.717 2.52 25.90
12 T0996TS344_2 21.91 2.58 25.48
13 T0996TS344_1 20.132 2.45 25.15
14 T0996TS322_3 22.115 2.57 25.15
15 T0996TS322_4 19.809 2.50 25.12
16 T0996TS196_2 23.262 2.45 24.97
17 T0996TS164_1 23 2.45 24.97
18 T0996TS135_2 22.893 2.45 24.97
19 T0996TS418_1 23.276 2.40 24.49
20 T0996TS244_2 23.276 2.40 24.49
21 T0996TS071_1 23.276 2.40 24.49
22 T0996TS441_3 23.276 2.40 24.49
23 T0996TS044_3 23.276 2.40 24.49
24 T0996TS344_4 19.186 2.58 23.95
25 T0996TS344_5 19.013 2.55 23.56
26 T0996TS441_1 23.087 2.35 23.26
27 T0996TS044_4 23.087 2.35 23.26
28 T0996TS354_1 19.01 2.48 22.21
29 T0996TS441_2 23.204 2.63 21.91
30 T0996TS196_5 23.891 2.63 21.91
31 T0996TS460_4 17.332 2.54 21.54
32 T0996TS460_1 19.03 2.22 21.51
33 T0996TS460_2 18.702 2.19 21.48
34 T0996TS460_3 19.246 2.25 21.45
35 T0996TS426_4 17.501 2.34 21.42
36 T0996TS460_5 18.553 2.22 21.39
37 T0996TS457_3 20.014 2.57 21.27
38 T0996TS055_4 17.966 2.39 21.24
39 T0996TS406_4 17.966 2.39 21.24
40 T0996TS145_4 17.966 2.39 21.24
41 T0996TS329_5 20.537 2.62 21.18
42 T0996TS164_2 20.462 2.64 21.12
43 T0996TS329_1 19.755 2.73 21.03
44 T0996TS397_1 21.056 2.65 20.94
45 T0996TS397_2 19.838 2.64 20.76
46 T0996TS441_5 20.912 2.25 20.76
47 T0996TS044_2 20.912 2.25 20.76
48 T0996TS044_5 20.319 2.32 20.73
49 T0996TS441_4 20.319 2.32 20.73
50 T0996TS116_1 18.335 2.64 20.73
51 T0996TS329_4 17.519 2.60 20.52
52 T0996TS222_4 18.831 2.35 20.19
53 T0996TS116_2 18.879 2.53 20.10
54 T0996TS089_1 19.127 2.45 20.07
55 T0996TS354_4 20.328 2.30 20.01
56 T0996TS192_3 20.087 2.49 19.95
57 T0996TS324_2 19.924 2.60 19.95
58 T0996TS222_2 18.493 2.33 19.92
59 T0996TS135_1 19.964 2.60 19.92
60 T0996TS196_1 19.964 2.60 19.92
61 T0996TS261_1 19.28 2.38 19.86
62 T0996TS222_5 19.246 2.26 19.86
63 T0996TS446_5 19.28 2.38 19.86
64 T0996TS197_2 19.598 2.56 19.83
65 T0996TS329_2 18.894 2.44 19.77
66 T0996TS224_4 19.176 2.57 19.74
67 T0996TS156_3 18.05 2.42 19.71
68 T0996TS192_4 18.125 2.44 19.65
69 T0996TS222_3 18.597 2.36 19.65
70 T0996TS156_1 18.117 2.44 19.65
71 T0996TS261_2 15.717 2.57 19.62
72 T0996TS156_2 18.467 2.39 19.47
73 T0996TS222_1 18.47 2.40 19.47
74 T0996TS214_1 17.722 2.35 19.44
75 T0996TS432_1 18.543 2.42 19.38
76 T0996TS261_5 19.572 2.45 19.32
77 T0996TS089_2 18.836 2.49 19.26
78 T0996TS208_3 16.979 2.38 19.20
79 T0996TS406_3 19.229 2.38 19.20
80 T0996TS055_5 19.229 2.38 19.20
81 T0996TS145_1 19.229 2.38 19.20
82 T0996TS224_1 19.641 2.42 19.14
83 T0996TS390_5 18.893 2.38 19.14
84 T0996TS156_4 18.611 2.50 19.11
85 T0996TS156_5 19.016 2.39 19.11
86 T0996TS192_5 18.611 2.50 19.11
87 T0996TS446_1 19.016 2.39 19.11
88 T0996TS085_1 16.943 2.48 19.05
89 T0996TS457_4 16.25 2.51 19.02
90 T0996TS246_4 15.523 2.36 19.02
91 T0996TS246_5 15.523 2.36 19.02
92 T0996TS470_1 19.683 2.20 18.96
93 T0996TS145_5 19.514 2.38 18.96
94 T0996TS390_3 17.862 2.49 18.90
95 T0996TS406_5 16.917 2.52 18.87
96 T0996TS055_1 16.917 2.52 18.87
97 T0996TS309_2 16.917 2.52 18.87
98 T0996TS086_2 16.917 2.52 18.87
99 T0996TS135_3 16.917 2.52 18.87
100 T0996TS390_4 16.835 2.43 18.87
101 T0996TS241_1 16.917 2.52 18.87
102 T0996TS368_2 16.917 2.52 18.87
103 T0996TS163_5 16.64 2.30 18.81
104 T0996TS055_3 17.457 2.19 18.81
105 T0996TS197_1 17.157 2.54 18.81
106 T0996TS368_3 17.457 2.19 18.81
107 T0996TS241_4 17.457 2.19 18.81
108 T0996TS086_3 17.457 2.19 18.81
109 T0996TS221_1 17.575 2.33 18.78
110 T0996TS446_3 17.575 2.33 18.78
111 T0996TS197_3 17.6 2.30 18.75
112 T0996TS163_4 17.379 2.40 18.72
113 T0996TS426_1 17.139 2.42 18.69
114 T0996TS457_2 19.026 2.31 18.69
115 T0996TS224_5 17.642 2.32 18.60
116 T0996TS208_2 17.352 2.33 18.57
117 T0996TS470_5 19.206 2.44 18.57
118 T0996TS241_3 18.409 2.25 18.45
119 T0996TS149_1 17.585 2.46 18.45
120 T0996TS309_3 18.409 2.25 18.45
121 T0996TS055_2 18.409 2.25 18.45
122 T0996TS446_4 18.409 2.25 18.45
123 T0996TS426_5 18.409 2.25 18.45
124 T0996TS368_1 18.409 2.25 18.45
125 T0996TS086_1 18.409 2.25 18.45
126 T0996TS044_1 18.409 2.25 18.45
127 T0996TS426_2 17.334 2.30 18.45
128 T0996TS406_2 18.409 2.25 18.45
129 T0996TS192_2 17.585 2.46 18.45
130 T0996TS208_5 17.432 2.57 18.42
131 T0996TS266_1 17.834 2.39 18.42
132 T0996TS354_2 19.809 2.09 18.42
133 T0996TS488_1 16.92 2.59 18.42
134 T0996TS470_4 18.867 2.35 18.42
135 T0996TS488_5 18.834 2.51 18.39
136 T0996TS470_2 18.732 2.27 18.39
137 T0996TS214_4 15.117 2.46 18.30
138 T0996TS274_1 17.555 2.40 18.24
139 T0996TS470_3 18.555 2.44 18.24
140 T0996TS197_5 17.658 2.30 18.24
141 T0996TS390_2 16.071 2.56 18.21
142 T0996TS160_1 19.105 2.51 18.18
143 T0996TS261_3 19.399 2.42 18.12
144 T0996TS426_3 19.301 2.36 18.12
145 T0996TS246_1 15.559 2.33 18.09
146 T0996TS246_2 15.559 2.33 18.09
147 T0996TS246_3 15.559 2.33 18.09
148 T0996TS208_4 17.932 2.28 18.06
149 T0996TS337_1 17.594 2.52 18.06
150 T0996TS208_1 17.819 2.35 18.03
151 T0996TS214_2 17.569 2.31 17.94
152 T0996TS266_3 17.616 2.53 17.91
153 T0996TS324_1 15.175 2.56 17.91
154 T0996TS197_4 18.692 2.39 17.91
155 T0996TS124_5 18.023 2.56 17.91
156 T0996TS471_4 15.3 2.32 17.88
157 T0996TS471_3 15.3 2.32 17.88
158 T0996TS274_2 16.737 2.14 17.88
159 T0996TS124_4 18.303 2.53 17.85
160 T0996TS124_1 17.712 2.44 17.79
161 T0996TS274_4 14.17 2.48 17.73
162 T0996TS116_5 21.437 2.34 17.73
163 T0996TS214_3 17.857 2.39 17.70
164 T0996TS124_2 18.047 2.57 17.70
165 T0996TS124_3 17.862 2.56 17.61
166 T0996TS457_1 16.529 2.49 17.49
167 T0996TS112_3 17.244 2.48 17.43
168 T0996TS116_4 17.792 2.60 17.37
169 T0996TS274_3 15.914 2.32 17.34
170 T0996TS047_1 18.511 2.32 17.31
171 T0996TS471_1 17.643 2.61 17.28
172 T0996TS471_2 17.643 2.61 17.28
173 T0996TS266_4 18.021 2.37 17.28
174 T0996TS224_3 14.312 2.63 17.25
175 T0996TS163_2 17.685 2.51 17.25
176 T0996TS266_2 17.574 2.56 17.22
177 T0996TS471_5 16.61 2.38 17.16
178 T0996TS112_4 16.45 2.66 17.16
179 T0996TS160_3 14.341 2.62 17.07
180 T0996TS163_1 14.976 2.49 17.01
181 T0996TS309_1 14.284 2.32 17.01
182 T0996TS488_2 14.284 2.32 17.01
183 T0996TS241_5 14.284 2.32 17.01
184 T0996TS112_5 17.314 2.55 16.98
185 T0996TS309_4 17.985 2.51 16.95
186 T0996TS488_4 17.985 2.51 16.95
187 T0996TS390_1 15.609 2.45 16.89
188 T0996TS274_5 15.129 2.34 16.89
189 T0996TS089_4 16.351 2.37 16.86
190 T0996TS112_2 16.39 2.63 16.77
191 T0996TS116_3 18.998 2.45 16.47
192 T0996TS457_5 16.482 2.50 16.41
193 T0996TS004_2 19.146 2.46 16.38
194 T0996TS214_5 15.763 2.52 16.38
195 T0996TS089_3 15.929 2.35 16.35
196 T0996TS112_1 18.124 2.62 16.35
197 T0996TS004_1 18.694 2.54 16.11
198 T0996TS023_3 16.677 2.10 15.99
199 T0996TS402_4 14.308 2.20 15.89
200 T0996TS402_2 15.351 2.18 15.80
201 T0996TS402_3 15.026 2.37 15.65
202 T0996TS402_5 15.065 2.33 15.54
203 T0996TS023_2 17.095 2.09 15.47
204 T0996TS402_1 14.952 2.28 15.47
205 T0996TS058_5 16.027 2.26 15.41
206 T0996TS472_3 15.483 2.42 15.32
207 T0996TS472_2 15.784 2.55 15.32
208 T0996TS472_1 15.972 2.39 15.26
209 T0996TS354_3 15.799 2.39 15.11
210 T0996TS145_3 15.356 2.35 15.02
211 T0996TS089_5 16.785 2.21 14.96
212 T0996TS452_2 14.361 2.58 14.93
213 T0996TS279_1 16.78 2.44 14.87
214 T0996TS058_4 13.338 2.39 14.84
215 T0996TS452_1 16.18 2.07 14.75
216 T0996TS243_3 14.071 2.13 14.60
217 T0996TS261_4 14.624 1.98 14.57
218 T0996TS145_2 15.823 2.43 14.42
219 T0996TS085_2 14.594 2.28 14.30
220 T0996TS135_4 13.552 2.48 14.21
221 T0996TS196_3 13.552 2.48 14.21
222 T0996TS023_1 13.751 2.24 14.21
223 T0996TS266_5 13.266 1.97 14.21
224 T0996TS043_3 13.404 2.09 13.82
225 T0996TS043_4 15.115 2.44 13.82
226 T0996TS243_4 13.976 2.11 13.79
227 T0996TS043_5 11.465 2.20 13.79
228 T0996TS354_5 14.207 1.83 13.76
229 T0996TS043_1 13.652 2.31 13.61
230 T0996TS337_5 14.757 2.59 13.37
231 T0996TS243_1 13.571 2.05 13.37
232 T0996TS023_5 13.802 2.04 13.37
233 T0996TS196_4 12.388 1.92 13.34
234 T0996TS337_4 16.343 2.54 13.34
235 T0996TS243_2 12.388 1.92 13.34
236 T0996TS337_2 14.515 2.28 13.31
237 T0996TS243_5 12.147 2.01 13.28
238 T0996TS043_2 11.902 2.09 12.74
239 T0996TS023_4 13.938 2.03 12.74
240 T0996TS058_3 12.052 2.17 12.35
241 T0996TS135_5 12.052 2.17 12.32
242 T0996TS322_5 12.535 2.44 11.81
243 T0996TS058_1 14.739 2.26 11.06
244 T0996TS498_3 7.783 2.70 10.73
245 T0996TS117_1 11.111 2.59 10.55
246 T0996TS498_1 7.586 2.85 10.16
247 T0996TS492_5 9.59 2.52 10.16
248 T0996TS058_2 9.672 2.16 10.01
249 T0996TS406_1 7.816 2.64 9.98
250 T0996TS498_4 7.816 2.64 9.98
251 T0996TS365_1 10.779 1.96 9.92
252 T0996TS498_2 10.263 2.31 9.80
253 T0996TS498_5 9.136 2.25 9.68
254 T0996TS492_2 9.366 2.64 9.62
255 T0996TS365_5 9.966 2.07 9.44
256 T0996TS365_3 9.756 2.19 9.38
257 T0996TS492_3 9.197 2.80 9.35
258 T0996TS365_4 9.193 2.19 9.13
259 T0996TS288_1 8.255 2.32 9.07
260 T0996TS492_1 10.628 2.46 8.92
261 T0996TS312_1 8.297 2.74 8.89
262 T0996TS365_2 9.416 2.05 8.77
263 T0996TS288_3 9.416 2.53 8.44
264 T0996TS224_2 9.27 2.49 8.41
265 T0996TS492_4 6.911 2.78 8.35
266 T0996TS288_4 6.395 2.50 8.02
267 T0996TS288_2 6.907 2.56 7.87
268 T0996TS288_5 5.87 2.56 7.33
269 T0996TS110_2 6.573 2.68 7.27
270 T0996TS110_4 10.596 1.77 7.09
271 T0996TS110_5 10.686 1.85 7.03
272 T0996TS110_1 9.767 2.03 6.91
273 T0996TS110_3 4.843 2.72 6.91
274 T0996TS381_5 7.119 2.86 5.38
275 T0996TS407_4 5.074 2.61 5.26
276 T0996TS407_2 5.177 2.84 5.26
277 T0996TS381_1 6.853 3.04 5.23
278 T0996TS381_4 7.008 2.63 5.14
279 T0996TS149_3 3.904 2.73 4.99
280 T0996TS381_2 7.55 2.73 4.96
281 T0996TS279_3 4.989 2.66 4.87
282 T0996TS351_4 4.697 2.69 4.78
283 T0996TS351_1 4.697 2.69 4.78
284 T0996TS351_2 4.697 2.69 4.78
285 T0996TS351_3 4.697 2.69 4.78
286 T0996TS351_5 4.697 2.69 4.78
287 T0996TS407_3 3.65 2.98 4.78
288 T0996TS279_2 4.564 2.76 4.60
289 T0996TS149_5 5.121 2.93 4.54
290 T0996TS407_5 4.509 2.53 4.45
291 T0996TS407_1 5.409 2.77 4.36
292 T0996TS149_4 4.852 2.56 4.36
293 T0996TS244_1 4.496 2.79 4.21
294 T0996TS279_5 4.304 2.45 4.21
295 T0996TS279_4 4.994 2.76 4.21
296 T0996TS368_4 4.496 2.79 4.21
297 T0996TS086_4 4.496 2.79 4.21
298 T0996TS071_2 4.496 2.79 4.21
299 T0996TS241_2 4.496 2.79 4.21
300 T0996TS418_2 4.496 2.79 4.21
301 T0996TS335_1 3.345 2.81 4.18
302 T0996TS149_2 4.681 2.56 4.18
303 T0996TS163_3 5.29 2.83 4.09
304 T0996TS160_2 5.887 2.65 4.06
305 T0996TS071_4 4.557 2.65 4.06
306 T0996TS381_3 5.895 2.88 4.06
307 T0996TS086_5 4.557 2.65 4.06
308 T0996TS368_5 4.557 2.65 4.06
309 T0996TS418_4 4.557 2.65 4.06
310 T0996TS160_5 3.801 2.68 3.97
311 T0996TS282_3 3.719 2.67 3.94
312 T0996TS244_4 3.719 2.67 3.94
313 T0996TS335_5 3.345 2.81 3.91
314 T0996TS071_3 5.342 2.72 3.91
315 T0996TS337_3 5.342 2.72 3.91
316 T0996TS418_3 5.342 2.72 3.91
317 T0996TS335_3 3.345 2.81 3.85
318 T0996TS335_2 3.345 2.81 3.79
319 T0996TS282_1 3.829 2.49 3.61
320 T0996TS377_2 3.345 2.81 3.61
321 T0996TS377_4 3.345 2.81 3.55
322 T0996TS377_3 3.345 2.81 3.49
323 T0996TS152_5 3.939 2.61 3.46
324 T0996TS377_5 3.345 2.81 3.46
325 T0996TS335_4 3.345 2.81 3.42
326 T0996TS282_5 5.136 2.84 3.40
327 T0996TS152_2 4.002 2.81 3.33
328 T0996TS152_1 4.342 2.90 3.19
329 T0996TS244_3 4.404 2.82 3.15
330 T0996TS358_1 4.253 2.96 3.15
331 T0996TS446_2 4.404 2.82 3.15
332 T0996TS418_5 4.404 2.82 3.15
333 T0996TS071_5 4.404 2.82 3.15
334 T0996TS488_3 4.404 2.82 3.15
335 T0996TS152_4 4.667 2.85 3.15
336 T0996TS152_3 4.653 2.67 3.12
337 T0996TS358_5 3.777 2.52 3.12
338 T0996TS282_2 4.208 2.66 3.10
339 T0996TS358_3 4.555 2.72 3.10
340 T0996TS348_4 4.291 2.55 3.10
341 T0996TS348_5 4.828 2.81 3.04
342 T0996TS472_4 5.711 2.79 3.04
343 T0996TS358_2 3.256 2.53 3.04
344 T0996TS312_3 5.008 2.62 2.98
345 T0996TS472_5 5.827 2.67 2.94
346 T0996TS282_4 3.004 2.80 2.94
347 T0996TS309_5 3.004 2.80 2.94
348 T0996TS348_3 4.207 2.85 2.94
349 T0996TS377_1 3.345 2.81 2.92
350 T0996TS312_2 4.57 2.95 2.92
351 T0996TS348_1 4.603 2.80 2.92
352 T0996TS312_5 5.126 2.74 2.92
353 T0996TS160_4 4.183 2.69 2.88
354 T0996TS378_4 4.073 2.57 2.88
355 T0996TS041_1 4.756 2.85 2.85
356 T0996TS348_2 4.477 2.66 2.85
357 T0996TS378_1 4.27 2.68 2.83
358 T0996TS378_2 4.782 2.74 2.83
359 T0996TS085_5 3.604 2.80 2.83
360 T0996TS312_4 5.265 2.91 2.79
361 T0996TS041_4 4.111 2.77 2.79
362 T0996TS041_2 4.343 2.73 2.76
363 T0996TS041_5 4.144 2.89 2.73
364 T0996TS497_3 7.265 2.73 2.73
365 T0996TS358_4 6.623 2.71 2.73
366 T0996TS378_5 4.403 2.80 2.70
367 T0996TS007_1 3.652 2.87 2.70
368 T0996TS497_1 5.58 2.72 2.70
369 T0996TS378_3 4.018 2.70 2.67
370 T0996TS041_3 4.097 2.82 2.61
371 T0996TS497_2 6.481 2.67 2.61
372 T0996TS244_5 3.854 2.73 2.58
373 T0996TS085_3 3.854 2.73 2.58
374 T0996TS085_4 4.626 2.60 2.58
375 T0996TS007_3 3.221 2.53 2.55
376 T0996TS458_5 4.132 2.54 2.55
377 T0996TS497_5 5.598 2.76 2.55
378 T0996TS458_4 5.73 2.70 2.49
379 T0996TS458_3 4.622 2.70 2.49
380 T0996TS497_4 6.944 2.83 2.34
381 T0996TS458_1 4.421 2.93 2.31
382 T0996TS007_2 3.466 2.77 2.31
383 T0996TS007_5 3.714 2.73 2.28
384 T0996TS458_2 4.011 2.87 2.25
385 T0996TS257_1 4.478 2.82 2.10
386 T0996TS257_5 4.933 2.59 2.07
387 T0996TS257_4 5.003 2.84 2.04
388 T0996TS007_4 3.238 2.80 2.04
389 T0996TS257_2 4.985 2.70 2.01
390 T0996TS257_3 4.788 2.70 1.92
Difference model - template
# Templates
1 5uvnE
2 5uw8F
3 5uw2C
4 1pj5A
5 1nkkA
6 5mznA
7 1njuA
8 1id4A
9 1pkyA
10 5tl4B
11 1pj6A
12 3ad7A
13 5x1mA
14 4pabB
15 1layA
16 1njtD
17 1a5uB
18 5x1kA
19 1nrkA
20 1iegA
21 1vlyA
22 4v07A
23 1at3A
24 1e0tC
25 2gagA
Protein Structure Prediction Center
Sponsored by the US National Institute of General Medical Sciences (NIH/NIGMS)
Please address any questions or queries to:
© 2007-2018, University of California, Davis