Principle of Biochemistry

In the beginning there was White, Handler, and Smith. (Biochemistry textbooks are almost never referred to by their titles, only by their authors. This point will be revisited shortly.) Then Mahler and Cordes provided competition. In 1970 (we are of course dealing in the distant mists of biochemical time), Lehninger appeared on the scene. It was considered by many to be the first “readable” biochemistry text and quickly became a popular staple in courses. Around the same time, as the inherent importance of biochemistry became obvious, textbooks started multiplying and getting larger. Biochemistry was in an impressive growth phase and authors felt the necessity to include the rapidly accumulating new information in their tomes without eliminating any of the old material.
This growth spurt of biochemistry and the accompanying texts soon resulted in a split of textbook style. Biochemistry was seen as crucial for most life science majors and even engineers needed to be enlightened. However, not all would need the rigorous approach presented by the early generations of texts. New books appeared where the title was now an issue. Volumes that were embossed with Outlines of …, Foundations in …, and Principles of … were aimed at the so-called non-majors sections of biochemistry. In 1982, Albert Lehninger decided that his original efforts had become too dense through two previous editions and opted for a third approach. He titled his new work Principles of Biochemistry but did not direct it toward non-majors. Rather, he saw the need for a book comprehensive enough for an attempt at complete coverage of the field, but not so in-depth that it could suffice as a graduate text. His new book would be designed for undergraduate biochemistry majors and others who needed a majors-level course.
This 4th edition of that newer Lehninger is the result of the evolution of this approach. Sadly, Albert Lehninger has not been around for recent editions but the book is wisely titled Lehninger Principles of Biochemistry. It still strives and, for the most part, succeeds in being a readable body of work. (On the other hand, it is something of an unfair criticism to say a text is unreadable. Very few will sit and read such a book like a novel. While students would gain the most from this approach—all texts endeavor for a coherent effort at tying biochemistry into a “big picture,” they are most likely to check out a specific section on a topic of misunderstanding, or, more likely, check out the index for the exact item in question.) Authors David Nelson and Michael Cox have built upon their previous edition to generate a smoothly flowing work.
Current users can rest assured that nothing drastic has been changed in style from the 3rd edition. However, there are important additions reflecting our still rapidly changing area of interest. Significant results from the Human Genome Project and other sequencing efforts are included. For example, ABC transporters in all organisms are now discussed. Genomics and proteomics are covered in a separate chapter, and new applications of methods such as atomic force microscopy are described. None of these new inclusions are forced in but seem to be blended nicely with existing material. Also blended in are new insights gained from structural determinations of complexes like bacterial RNA polymerase and large and small ribosomal subunits. The importance of structure in the understanding of biochemical principles was recognized early by Lehninger and is continued by the authors as shown by their inclusion of the Protein Data Bank identification code for each structure shown in the text. The authors have also greatly expanded their coverage of detailed reaction mechanisms.
Instructors should note that the much of the 3rd edition's initial four-chapter section on foundations of biochemistry has been combined and dispersed to other chapters. There is now one initial chapter called “The Foundations of Biochemistry” followed by one devoted to water. The cell biology information in the old chapter two has been placed in the context of other chapters and reduced in scope. Likewise, much of the chemistry found in the old chapter three has been placed in other locations. One presumes the authors have decided to recognize the fact that other courses in fundamentals of chemistry and organic chemistry should be prerequisites for a course using their text. These reductions and combinations are probably ways to get to the meat of the subject more quickly and keep the volume to a manageable size.
With any text of such scope, there are always small things that can be changed. For instance, the authors incorporated essentially intact their section on DNA fingerprinting from the older edition. This shows Southern blotting and RFLP analysis on autoradiograms. This method has long been supplanted by using PCR and capillary electrophoresis.
No modern text book would be complete without the accompanying flock of supplements and this one is no exception. There is a study guide and separate lecture notebook to make life easier for students, a set of transparencies (with bold writing for good projection characteristics) and two test banks to make life easier for the instructor, and a website with graphics and animations to make life easier for both. The website is linked to the appropriate site in the text with an icon of a mouse (computer, not mammalian).
There are too many good biochemistry text books in the market to allow any bad ones to survive. They will all cover essentially the same material in slightly different (and sometimes identical) ways. New editions are ways for books to incorporate new material and feedback from previous versions and it seems that Nelson and Cox have done both in an admirable fashion. This text should continue to please users of the older versions and continue the model that Lehninger himself established with his first efforts.
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Since its first edition in 1975, this extraordinary textbook has helped shape the way that biochemistry is taught, and has become one of the most trusted books in the field. It offers exceptionally clear writing, innovative graphics, coverage of the latest research techniques and advances, and a signature emphasis on physiological and medical relevance. The seventh edition has been updated throughout, including many new advances on genetic regulation, and revamped coverage of the integration of metabolism in the context of diet and obesity. Numerous new medical examples have been added throughout to make biochemistry real and relevant to students. The addition of new contributing author Gregory Gatto, an active pharmaceutical researcher at GlaxoSmithKline, ensures that the seventh edition presents the latest techniques that students need to understand in biochemistry research today. The end-of-chapter problems have also been revised and updated, providing students with great new exercises to test their understanding. The book is supported by a companion website ( which provides a variety of tools to aid understanding and learning including concept-based tutorials, animated techniques, self-assessment tools, and living figures that allow protein structures to be explored in 3-D.
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Apa itu File Format .djvu dan bagaimana membukanya?

Djvu (dibaca “Deja vu”) adalah suatu set yang terdiri dari teknologi kompresi, sebuah format file (.djvu) dan sebuah software platform untuk pengiriman ke Web yang terdiri dari digital documents, scanned documents, dan high resolution images

Djvu dokumen men-download dan menampilkan secara cepat, tepat dengan tampilan sama pada semua platform tanpa masalah kompatibilitas karena font, warna, dan lainnya. DjVu bisa menjadi alternatif yang lebih unggul dari Software lainnya dalam menampilkan format-format tertentu. Di antaranya adalah :
DjVu lebih baik dari PDF dan PostScript dalam menampilkan dokumen digital
DjVu lebih baik dari TIFF (dan PDF) dalam menampilkan scanned bitonal documents
DjVu lebih baik dari JPEG2000 dan JPEG dalam menampilkan foto dan gambar
DjVu lebih baik dari GIF dalam menampilkan large palettized images
Djvu adalah satu-satunya web format yang praktis untuk mendistribusikan high-resolution scanned documents yang berwarna. Tidak ada web format lain yang dapat menandinginya dalam hal ini.
Kelebihan Type File .djvu adalah sebagai berikut:
Bitonal Scanned Documents : 5 - 30KB per halaman di 300dpi (3 - 10 kali lebih kecil dari .PDF atau .tiff)
Color Scanned Documents : 30 - 100KB per halaman di 300dpi (5 - 10 kali lebih kecil dari .JPEG).
Foto: 2 kali lebih kecil dari JPEG, hampir sama dengan ukurang JPEG-2000, tetapi decoder / renderer DjVu progresif dan memiliki persyaratan memori yang lebih kecil.
Palettized Images : 2 kali lebih kecil daripada .GIF ( bisa samapi 10 kali jika isinya kebanyakan teks).
Digital (non scanned) Documents : antara 1 - 3 kali lebih kecil dari .PDF atau gzipped PS (tergantung jumlah gambar), tetapi page flipping, zooming, panning jauh lebih cepat, dan kualitas gambar pada layar tampilan jauh lebih baik (antialiased teks, dan lainnya).
Kelebihan lainnya yang bisa dibilang yang terpenting adalah bahwa file djvu dapat dengan cepat diload, sehingga melihat dokumen menjadi jauh lebih menyenangkan.
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Penelitian Ilmiah

Makna Penelitian Ilmiah

Ilmu pengetahuan merupakan produk dari penelitian baik ilmu pengetahuan alam maupun ilmu pengetahuan sosial. Penelitian ilmiah merupakan bagian tak terpisahkan dari ilmu pengetahuan. Citra orang tentang ilmu pengetahuan sangat tergantung pada bagian penting yang merupakan wajahnya yaitu kegiatan penelitian ilmiah.

Penelitian ilmiah adalah penelitian yang mengandung unsur‐unsur ilmiah atau keilmuan di dalam aktivitasnya. Ostle pada Nazir (1999), menyatakan penelitian yang dilakukan dengan menggunakan metode ilmiah (scientific methode) disebut penelitian ilmiah, mengandung dua unsur penting yakni; unsur pengamatan (observation) dan unsur nalar (reasoning). Penelitian ilmiah juga berarti penyelidikan yang sistematis, terkontrol, empiris, dan kritis tentang fenomena‐fenomena alami, dengan dipandu oleh teori‐teori dan hipotesis‐hipotesis tentang hubungan yang dikira terdapat diantara fenomena‐fenomena itu (Kerlinger, 2000). Penelitian ilmiah merupakan mesin yang memproses produk ilmu pengetahuan. Dapat disimpulkan bahwa Penelitian ilmiah merupakan serangkain kegiatan sistematis yang didasarkan pada metode ilmiah dengan tujuan mendapatkan jawaban secara ilmiah terhadap permasalahan atau pertanyaan penelitian yang diajukan sebelumnya. Tentunya ada banyak cara menemukan jawaban yang dimaksud, variasi cara penelitian terjadi tidak hanya dalam penelitian ilmiah terjadi tidak hanya dalam penelitian dalam bidang yang sama, malahan tentang yang sama.

Ilmiah berarti kegiatan penelitian didasarkan pada ciri‐ciri keilmuan (Sugiyono,1999), diantaranya: 
1. Rasional: penyelidikan ilmiah adalah sesuatu yang masuk akal dan terjangkau oleh penalaran manusia. Polisi menyelidiki kasus pencurian dan menemukan pencuri adalah contoh yang masuk akal, tetapi paranormal menemukan dalam menemukan pencuri atau barang yang hilang adalah tindakan yang tidak masuk akal manusia. 
2. Empiris: menggunakan cara‐cara tertentu yang dapat diamati orang lain dengan menggunakan panca indera mereka. Paranormal berusaha menemukan pesawat yang jatuh di Sibolangit bukan merupakan cara empiris, karena tidak kita dapat mengamati bagaimana proses paranormal tersebut dalam menemukan pesawat tersebut. 
3. Sistematis: menggunakan proses dengan langkah‐langkah logis. Proses yang dilakukan dalam penelitian ilmiah berawal dari penemuan masalah, merujuk teori, mengemukakan hipotesis, mengumpulkan data, menganalisis data, dan membuat kesimpulan

Beberapa karakteristik umum yang dimiliki Metode Ilmiah : 
• Kritis dan Analitis : Mendorong suatu kepastian dan proses penyelidikaan untuk megidentifikasi masalah dan solusinya. 
• Logis : Merujuk pada metode dari argumentasi ilmiah dan kesimpulan rasional dari bukti‐ bukti yang ada. 
• Objektif : Bahwa yang diperoleh ilmu lain akan sama apabila studi yang samaadilakukan padaa kondisi yang sama. 
• Konseptual dan teoritis : Menuntun dan mengarahkan upaya penelitian. 
• Empiris : Bersandar pada realitas. • Sistematis : Prosedur yang cermat dan aturan baku

Penemuan kebenaran ilmiah dimaksudkan untuk memperoleh : 
1. scientific object yang bermaksud memperkaya khasanah ilmu pengetahuan. 
2. practical objective bertujuan untuk memecahkan problema praktikal yang mendesak. Untuk memperoleh kebenaran ilmiah dikembangan metode ilmiah yang memilki pola umum sebagai berikut ;
Penarikan kesimpulan hasil penelitian ada 2 pola yaitu :
• Deduktif : Penarikan kesimpulan untuk hal spesifik dari gejala umum. 
• Induktif : Penarikan kesimpulan berdasar keadaan spesifik untuk hal‐hal umum.Beberapa hal yang termasuk pada bagian ini adalah menaksir, meramalkan, menguji hipotesis dan hubungan antara beberapa variabel.

semoga bermanfaat:


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