Tài liệu PDF How Hormones Work

7.2. Building Your Own Workflow You could spend all day playing with the workflows Apple gives you, making minor tweaks and seeing how they affect the workflow's progress. You could even download more preassembled workflows from www.automatorworld.com , macscripter.net, or Apple's own www.automator.us , if you were so inclined. Still, those options don't give you the kind of hands-on experience you need if you ever want to automate your Mac on your own. That's why the following pages walk you through building three different Automator workflows from scratch. Along the way, you'll learn several tricks that you'll find handy when you start building your own workflows. Tip: If you're feeling lazy, you can download the completed workflow projects from this book's "Missing CD" page atwww.missingmanuals.com . 7.2.1. Emailing an iTunes Song So you're listening to a song in iTunes, and you're seized by an overwhelming urge to email it to someone. Maybe you think your mom would like to hear the new Britney Spears hit (hey, she's your mom), or that your brother would be interested in your latest GarageBand opus (he probably isn't). The traditional process for emailing a song is a huge pain: locating the song in iTunes, Control-clicking it, choosing Show in Finder from the shortcut menu, creating a new message in Mail, addressing it, typing out a subject and short body message, dragging the song file from the Finder into the email message, and, finally, clicking Send. Life's too short. Automator can greatly simplify this process. With a simple two-action workflow, you can locate a song from your iTunes Library, set up all the email information you want in a dialog box, and have Automator attach the song file automatically. Figure 7-8 shows what the final workflow looks like. Figure 7-8. Your new workflow lets you pick a song in your iTunes Library (top), and then attach the song to a new email message. This action is a heck of a lot easier than trying to do all the steps manually. Note: Your recipient may not be able to play the song if it came from the iTunes music store. Those songs are copy-protected, and play back on a maximum of five computers. (MP3 files, GarageBand compositions, and songs you've ripped from your own CDs, of course, have no such restrictions.) Here's how to build the workflow: 1. Open a new Automator workflow window. Either choose File New or press -N. 2. In the Starting Points menu, click Music & Audio. From the "Get content from"pop-up menu, choose "my iTunes Library. "Then, from the second pop-up menu, choose "Ask for songs and playlists when my workflow runs." Since you're not looking for music files in the Finder or on the Web, you want Automator to look specifically at your iTunes Library. The second pop-up menu gives you a bunch of options for how and when you want to specify which song(s) to use in the workflow. These options are pretty self-explanatory: You can either select or search for songs, and you can either do so right now or when you run the workflow. Since you'll probably want to use this workflow more than once, and for different songs, you want the ability to select a song every time the workflow runs. When you click Choose, How Hormones Work How Hormones Work Bởi: OpenStaxCollege Hormones mediate changes in target cells by binding to specific hormone receptors In this way, even though hormones circulate throughout the body and come into contact with many different cell types, they only affect cells that possess the necessary receptors Receptors for a specific hormone may be found on many different cells or may be limited to a small number of specialized cells For example, thyroid hormones act on many different tissue types, stimulating metabolic activity throughout the body Cells can have many receptors for the same hormone but often also possess receptors for different types of hormones The number of receptors that respond to a hormone determines the cell’s sensitivity to that hormone, and the resulting cellular response Additionally, the number of receptors that respond to a hormone can change over time, resulting in increased or decreased cell sensitivity In up-regulation, the number of receptors increases in response to rising hormone levels, making the cell more sensitive to the hormone and allowing for more cellular activity When the number of receptors decreases in response to rising hormone levels, called down-regulation, cellular activity is reduced Receptor binding alters cellular activity and results in an increase or decrease in normal body processes Depending on the location of the protein receptor on the target cell and the chemical structure of the hormone, hormones can mediate changes directly by binding to intracellular hormone receptors and modulating gene transcription, or indirectly by binding to cell surface receptors and stimulating signaling pathways Intracellular Hormone Receptors Lipid-derived (soluble) hormones such as steroid hormones diffuse across the membranes of the endocrine cell Once outside the cell, they bind to transport proteins that keep them soluble in the bloodstream At the target cell, the hormones are released from the carrier protein and diffuse across the lipid bilayer of the plasma membrane of cells The steroid hormones pass through the plasma membrane of a target cell and adhere to intracellular receptors residing in the cytoplasm or in the nucleus The cell signaling pathways induced by the steroid hormones regulate specific genes on the cell's DNA The hormones and receptor complex act as transcription regulators by increasing or decreasing the synthesis of mRNA molecules of specific genes This, in turn, determines the amount of corresponding protein that is synthesized by altering 1/6 How Hormones Work gene expression This protein can be used either to change the structure of the cell or to produce enzymes that catalyze chemical reactions In this way, the steroid hormone regulates specific cell processes as illustrated in [link] Art Connection An intracellular nuclear receptor (NR) is located in the cytoplasm bound to a heat shock protein (HSP) Upon hormone binding, the receptor dissociates from the heat shock protein and translocates to the nucleus In the nucleus, the hormone-receptor complex binds to a DNA sequence called a hormone response element (HRE), which triggers gene transcription and translation The corresponding protein product can then mediate changes in cell function Heat shock proteins (HSP) are so named because they help refold misfolded proteins In response to increased temperature (a “heat shock”), heat shock proteins are activated by release from the NR/HSP complex At the same time, transcription of HSP genes is activated Why you think the cell responds to a heat shock by increasing the activity of proteins that help refold misfolded proteins? Other lipid-soluble hormones that are not steroid hormones, such as vitamin D and thyroxine, have receptors located in the nucleus The hormones diffuse across both the plasma membrane and the nuclear envelope, then bind to receptors in the nucleus The hormone-receptor complex stimulates transcription of specific genes Plasma Membrane Hormone Receptors Amino acid derived hormones and polypeptide hormones are not lipid-derived (lipidsoluble) and therefore cannot diffuse through the plasma membrane of cells Lipid insoluble hormones bind to receptors on the outer surface of the plasma membrane, via plasma membrane hormone receptors Unlike steroid hormones, lipid insoluble 2/6 How Hormones Work hormones not directly affect the target cell because they cannot enter the cell and act directly on DNA Binding of these hormones to a cell surface receptor results in activation of a signaling pathway; this triggers intracellular activity and carries out the specific effects associated with the hormone In this way, nothing passes through the cell membrane; the hormone that binds at the surface remains at the surface of the cell while the intracellular product remains inside the cell The hormone that initiates the signaling pathway is called a first messenger, which activates a second messenger in the cytoplasm, as illustrated in [link] ... But it's not so great if you want to hand the CD or DVD to anyone who doesn't use iPhoto (like a Mac OS 9 person or a Windows person), because they'll have a devil of a time figuring out where all the photos are in the convoluted Library folder structure. If you build an Automator workflow to back up your photos instead, you (a) can burn a disc containing only the photos in one simple folder; (b) have more control over which photos are backed up; and (c) learn even more tricks for automating sophisticated operations. Figure 7-10 shows what the final workflow looks like. Here's how to put it together: 1. Create a new Automator workflow ( -N). The Starting Points screen appears. 2. Click Photos & Images. From the "Get content from" pop-up menu, choose "my iPhoto Library. "From the second pop-up menu, choose "Ask for photos and albums when my workflow runs." Click Choose. Your newly hatched workflow, when it runs, will begin by asking you which photos you want to back up when you run the workflow. Tip: What you really want is to round up only the latest batch of photos—since your last backup, for example. Fortunately, one of the actions in the Photos folder is called Find iPhoto Items, and it lets you specify a time period like "Within the last 2 weeks." It would be perfect for this workflow—if it weren't so buggy. (For example, it finds multiple copies of each photo.)For best results, then, create a Smart Album in iPhoto that lets you filter photos based on certain criteria—all your photos taken in the past two months, for example. When you run the workflow, you can choose that album to back up, so that you get only the most recent shots. 3. In the Library list, click the Utilities folder. Drag the Ask for Confirmation action into the Workflow pane, above the Ask for Photos action. Fill in the text as shown at the top of Figure 7-10 . You want to drag it above the Ask for Photos action so it's the first thing that happens when you run your workflow. Now you've just directed Automator to begin its work by displaying a dialog box (Figure 7-11 ). Figure 7-11. The explanatory dialog box from the iPhoto Backup workflow. Making the dialog box appear is optional, but it's helpful if you come back to your workflow in a few months and forget what it's supposed to do. 4. Drag the "Burn a Disc" action to the bottom of the Workflow pane. This action takes the images you selected in the Ask for Songs action and burns them to a CD or DVD. 5. In the Disc Name field of the Burn a Disc action, type "iPhoto Backup from "(that's a space after "from"). The workflow will complete this phrase later. 6. Click Variables above the Library list. Those variables are about to come in handy. You're going to complete the phrase "iPhoto Backup from" with whatever the date of the backup is. 7. Click the Date & Time folder in the Library list. Drag the "Today's date" variable into the Disc Name field after "from." The CD or DVD's name will be something like "iPhoto Backup from 4/9/08,"making it easy for you to see when you made the backup disk. The date automatically changes whenever you run the workflow. When you click Run, your workflow springs into action. If there isn't a blank CD or DVD in your Mac, Automator asks for one. Skip to Section 7.4 to see how to save the result as a double-clickable icon on your desktop. 7.2.3. Converting and Renaming Images This workflow is the most complicated of these examples, but also the one that saves you the most time. It processes any set of graphics files by converting them to the space- saving JPEG format, shrinking them to reasonable pixel dimensions for sending by email or posting on The Photoshop Lightroom Workbook 32 and every photographer used Polaroid  lm on a shoot. Operating systems continually change. On the MAC side, we have gone from Panther to Tiger to Leopard in less than 5 years. No camera manufacturer has guaranteed that all current software will be backward compatible. Files that opened up on your OS 9 system may not open up today. Digital needs to be as stable as  lm. Only a standard  le format can assure this for the future. Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. 33 CHAPTER 3 Color Spaces for Digital The Four Color Spaces for Digital T here are four color spaces that we will discuss: sRGB, Adobe98, ColorMatch and ProPhoto. First, think about color spaces as boxes of Crayola crayons. sRGB is the smallest box of crayons. It has 256 tones. The large box that many people choose can be thought of as Adobe98. It is like the big box of crayons with many shades of the same color. The ColorMatch space can be thought of as a much bigger box than sRGB but not as big as Adobe98. Finally, there is the ProPhoto color space, which is so big that not all the colors can even  t in the box. Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. The Photoshop Lightroom Workbook 34 Understanding Raw Digital Capture R a w  les contain no color pro le upon capture. Once you bring those raw  les into an image-processing software such as Lightroom, a color space needs to be designated. ProPhoto is D-65’s choice for processing raw  les. We also set up our color settings in Photoshop with ProPhoto as our working RGB. Why? Digital cameras today have come a long way in a very short time. The sensors today are capable of capturing a very wide tonal range, but unfortunately, the majority of photographers simply don’t take advantage of the capabilities of their camera sensors and inadvertently throw out very important color information without even realizing it. Your camera captures a wider range of colors than you can see. The pro le associated with the camera determines the colors available to be processed. Your camera captures a wider range of colors than your monitor can display. The pro le associated with the monitor determines what colors presented to it are actually to be displayed. Your camera captures a wider range of colors than your printer can print. The pro le associated with the printer determines which of the colors presented to it will be printed. Let’s start with how most cameras actually capture color or rather don’t capture color. The camera sensor doesn’t actually capture color at all. The sensor captures in grayscale only. It captures the intensity of the light in grayscale. There are colored  lters on the sensor such that a given pixel only sees light through a single colored  lter: either red or green or blue. Assuming you are shooting RAW, the job of the converter such as Lightroom, Adobe Camera Raw or Capture One is to interpolate data and render it as color. If the pixel being interpolated is a ‘ red ’ pixel, that value is assigned red. If the pixel being interpolated is a ‘ green ’ pixel, that value is assigned green, and if the pixel being interpolated is a ‘ blue ’ pixel, the value being assigned is blue. With these three values, a color equivalent number can be calculated. Every camera requires a pro le or formula that can be used to translate the ‘ zeros and ones ’ that become color equivalent numbers. Monitors and printers must recognize those numbers. This translation is essentially the goal of your working space. Okay, so in a more basic English, the color world we perceive with our eyes is captured by The Photoshop Lightroom Workbook 182 all the color channels. This panel also has a Targeted Adjustment Tool, which works great! You can create any black and white e ect you have ever dreamed of. The Split Toning Panel Using the split toning controls on images after they have been converted to monochrome allows you to add some color to the image. You can independently control the hue shift and saturation of Highlights and Shadows. The Hue Sliders adjust the hue and the Saturation Sliders can be used to apply varying degrees of color tone. The Balance Slider balances the e ect between the Highlights and the Shadows. A positive number on the Balance Slider increases the e ect of the Highlights Slider, while a negative number increases the e ect of the Shadows Sliders. This tool is useful for creating Black and White e ects such as Sepia, Brown Tone, Warm Tone, Cool Tone, etc. These adjustments can be saved as a Custom Preset and used again later. You can create your own ‘ look ’ to use over and over again. Of course you can do this on color images as well allowing you to warm highlights and cool shadows. Using Split Toning 1. Hold the option button down, and mouse down on hue. 2. If you drag the slider back and forth, you will see the hue change. Find a hue you like for the highlights and release the mouse. 3. Now go to the Saturation Slider, starting at 0. 4. Drag the slider to the right until you have the appropriate saturation of the hue. 5. Do the same thing for the shadows ( Figure 8.50 ) . The Detail Panel Sharpening The Detail Panel in Lightroom allows you to sharpen using Amount, Radius, Detail and Masking with the use of sliders. The detail panel also incorporates Noise Reduction and Chromatic Aberration. The Sharpening Panel has a default set for raw  le processing because most raw  les need some degree of sharpening. We’ll explain why. Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. The Develop Module 183 When photons are digitized to pixels, sharpness is lost because regardless of how large the sensor is, pixels are sampled as a  xed grid of graytones that mimic the continuous graduations of color perceived by the human eye into shape-speci c pixels. This process of digitalization is accomplished by reconstructing data at a ‘ frequency ’ that produces aliasing or nonalignment. Hence, most cameras today deploy an anti-aliasing  lter that eliminates the highest frequency detail. The net e ect is the detail rendered appears soft. So digital photographs look soft because of the very nature of pixel. For this reason we typically want to capture sharpen-de ning basic focus restoring any sharpness that was lost in the capture process. The Sharpening Default for Lightroom is: ● Amount 25 ● Radius 1.0 ● Detail 25 ● Masking 0 When sharpening, it is critical to set the zoom level to 100% or greater in order to view the e ects of the sharpening controls. A general rule when doing sharpening is to sharpen pixels without adding any ugly artifacting. New in Lightroom 2.0 is a magni cation window right in the Sharpening Panel. You can click Black and white images can be adjusted using the Grayscale mix and color can be applied to the image using split toning. FIG 8.50 Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. The Photoshop Lightroom Workbook 184 on the little button in the upper left-hand corner and wherever your cursor moves will be magni ed in the window. A mouse click locks the focus on a speci c point ... Unlike steroid hormones, lipid insoluble 2/6 How Hormones Work hormones not directly affect the target cell because they cannot enter the cell and act directly on DNA Binding of these hormones to... misfolded proteins? Other lipid-soluble hormones that are not steroid hormones, such as vitamin D and thyroxine, have receptors located in the nucleus The hormones diffuse across both the plasma... Amino acid derived hormones and polypeptide hormones are not lipid-derived (lipidsoluble) and therefore cannot diffuse through the plasma membrane of cells Lipid insoluble hormones bind to receptors