Pages 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 18661 result(s) returned

4.3 The UK's coal reserves

Production of large quantities of coal in the UK during the 19th and 20th centuries led to the progressive depletion of reserves. In 2005 underground mining was limited to the Carboniferous coalfields of Yorkshire and the East Midlands, with only one underground mine operating in South Wales. However, surface mining sites still work coal in most of the coalfields (Author(s): The Open University

4.1 Global coal reserves

Having looked in detail at how coal is mined, this section focuses on those areas of the world that produce it. It begins by looking at how and why reserves of coal are distributed throughout the UK and Europe, before reviewing the current global reserves of coal.


Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

1.4 Coal-forming environments in the geological record

Figure 5 simplifies a typical vertical succession of sedimentary rocks found in many coalfields. The sequence from the base of the section upwards reveals the following:

  1. When a mire starts to form, the first plants take root in underlying clays or sands that form the soil. Their rootlets are p
    Author(s): The Open University

    License information
    Related content

    Copyright © 2016 The Open University

Conclusion

This free course provided an introduction to studying the arts and humanities. It took you through a series of exercises designed to develop your approach to study and learning at a distance and helped to improve your confidence as an independent learner.


Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

7.4 Proteomics

Traditionally, the study of the biochemistry or structure of a protein necessitated its purification to a high degree. The development of protocols for cloning, manipulation and expression of genes greatly facilitated this kind of study, as will be clear to you from the previous section. In recent years, a number of high-throughput techniques have, to an extent, obviated traditional approaches and permit simultaneous analysis of all the expressed proteins in a cell or organism, known as the <
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

7.3.1 Physical methods for demonstrating an interaction between proteins

To identify those unknown proteins in a complex mixture that interact with a particular protein of interest, protein affinity chromatography can be used (Figure 49a). This approach uses a ‘bait’ protein attached to a matrix. When this baited matrix material is then exposed to a mixture of proteins, only proteins that interact with th
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

2.4 The covalent modification of proteins

Many proteins are modified by the covalent linking of groups that can affect their function and/or localisation in the cell. Such covalent modifications occur after synthesis and folding of the polypeptide component. The main types of covalent modification and their functions are listed below.

  1. Methylation/acetylation of amino acids at the N-terminal tails of histone proteins in eukaryotes can affect the structure of chromatin and ultimately gene
    Author(s): The Open University

    License information
    Related content

    Copyright © 2016 The Open University

1.3.1 Helices

A variety of helical structures can be identified in proteins using X-ray diffraction. A helix can be described by the number of units (amino acid residues) per turn (n) and by its pitch (p), which is the distance that the helix rises along its axis per turn. These parameters are indicated in Figure 8 for a number of helice
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

1.2 The peptide bond and primary structure of proteins

The primary structure of a protein is defined as the sequence of amino acids of which it is composed. This sequence ultimately determines the shape that the protein adopts, according to the spatial limitations on the arrangement of the atoms in the protein, the chemical properties of the component amino acid residues, and the protein's environment.

The peptide bonds that link amino acid residues in a polypeptide are formed in a condensation reaction between the acidic carboxyl gr
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

3.3.1 Phosphatidylinositol 3-kinase (PI 3-kinase)

Members of this family of lipid kinases usually have two subunits: one is a catalytic subunit with a lipid kinase domain and the other is a regulatory subunit, which contains two SH2 domains and a SH3 domain (p 85 PI 3-kinase in Figure 13).

  • Author(s): The Open University

    License information
    Related content

    Copyright © 2016 The Open University

2.3.2 Seven-helix transmembrane (7TM) receptors

Although in unicellular organisms such as the yeast S. cerevisiae there are only two classes of 7TM receptors, the pheromone and glucose receptors, multicellular organisms have many more, accounting for up to 5% of all genes in C. elegans and 2% of genes in the human and Drosophila genomes. 7TM proteins have been classified into four classes, A, B, C (Table 1). Between them, they can bind a huge range of ligands including simple ions, nucleotides, lipids, steroids, modifi
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

2.3 Receptor activation

Receptors may be activated by conformational change (for example, ion-channel receptors such as nicotinic receptors, and 7TM receptors such as muscarinic receptors and adrenergic receptors), by formation of dimers (such as receptors with intrinsic enzymatic activity and recruiter receptors) or by proteolysis. We shall now consider how each cell surface receptor class described in Author(s): The Open University

7.1 Blackbody radiation

Interpretation of the light astronomers collect from AGN depends on understanding the physical processes leading to the emission of that light. Because the conditions in the emitting regions of AGN are very different from those on the surface of the Earth, some of these processes may be entirely unfamiliar to you. This subsection begins with a discussion of blackbody radiation, which should be familiar, and covers material which you will need to appreciate Peterson's discussion of AGN.


Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

1 Meet your first active galactic nuclei

Figure 1 compares two nearby spiral galaxies of similar distance and type. NGC 5548, on the left, has a brighter nucleus than that of NGC 3277, on the right. This extra emission from the central regions of NGC 5548 is not generated by stars. Instead this light is thought to be ultimately powered by material falling in the gravitational field of
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

3.4 Predicting the outcome of crosses

By knowing the pattern of inheritance of genes as described above, it is possible to make some predictions about the phenotypes and genotypes of each generation in breeding experiments. This section considers some examples of such predictions.

First consider whether it is possible to determine the genotype for certain characters, such as grain colour, from observing an organism's phenotype.

Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

5.2 Alpha decay

You have probably met the law of radioactive decay, which says that, given a sample of N0 similar nuclei at time t = 0, the number remaining at time t is N(t) = N0eλt, where λ, the decay constant for a particular kind of nucleus, determines the rate at which the nuclei decay. The half-life is the time needed for half of any sufficiently large sample to decay. It is related to the de
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

3.5 Scattering from finite square wells and barriers

The procedure used to analyse scattering from a finite square step can also be applied to scattering from finite square wells or barriers, or indeed to any combination of finite square steps, wells and barriers. The general procedure is as follows:

  • Divide the x-axis into the minimum possible number of regions of constant potential energy.

  • Write down the general solution of the relevant time-independent Schrödinger equation in
    Author(s): The Open University

    License information
    Related content

    Copyright © 2016 The Open University

Acknowledgements

The organisers of this course are grateful for the financial support provided by the Royal Society, whose generous backing covered all aspects of the course's production and presentation.

The material acknowledged below is Proprietary and used under licence (not subject to Creative Commons licence). See terms and conditions. This content is made available under a
Author(s): The Open University

Derived functions and derivative notation

Given the function x(t) that describes some particular motion, you could plot the corresponding position-time graph, measure its gradient at a variety of times to find the instantaneous velocity at those times and then plot the velocity-time graph. If you had some time left, you might go on to measure the gradient of the velocity-time graph at various times, and then plot the acceleration-time graph for the motion. This would effectively complete the description of the motion, b
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

3.7 A note on straight-line graphs and their gradients

We end this section by reviewing some of the important features of straight-line graphs, though we do so in terms of two general variables z and y, rather than x and t, in order to emphasise their generality. If the graph of z against y is a straight line of the kind shown in Figure 22, then z and y are related by an equation of the form

<
Author(s): The Open University

License information
Related content

Copyright © 2016 The Open University

Pages 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934