Letter Code Research Articles

On the role of word frequency in the detection of component letters

The experiments reported in this study were conducted to explore the issue of race models versus holistic models of word processing. In both types of model, it is assumed that an available word-level encoding for a display will conceal letter information, and thereby inhibit component-letter detection. However, whereas in holistic models it is assumed that encoding always should occur at the word or pattern level first, in the race models it is assumed that encoding occurs at all levels (e.g., feature, letter, and word) simultaneously, with the final level of encoding being at whatever level has been completed first. If the rate of word-level encoding is facilitated by increasing word frequency, the holistic models predict a generally declining latency for letter detection, because the initial step in letter detection (i.e., word-level encoding) will be occurring more rapidly. The race models, on the other hand, predict that with increasing word frequency there will be an increasing chance that the word-level encoding will win the encoding race, resulting in an increase in the latency for letter detection (i.e., the word code will conceal the letter codes). Two experiments are reported, and the obtained pattern of latency data appears to be most consistent with the race models.

EPPO crop growth stage keys Echelles OEPP des stades de développement des plantes cultivées

Three scales were included in the original key published in Bulletin OEPP/EPPO Bulletin 14, 291–294, i.e. the scale of Fleckinger, a Belgian scale and a British one. In this revised version, a scale from the German Democratic Republic, similar to these in the use of letter codes, is added and all four are compared to a decimal scale from the Federal Republic of Germany.The decimal scale is presented in Table 1 with the codes of the other four scales presented alongside for direct comparison. Table 2 reprints the Fleckinger, Belgian and British scales with the equvalent stages of the FRG scale alongside. Illustrations from the two German scales are added.

Written spelling agraphia

When a disorder of single word writing is seen in conjunction with preserved oral spelling and intact written grapheme formation (“written spelling agraphia”), the deficit may be presumed to lie somewhere between letter choice and written motor output. Two potential deficits are considered: (1) visual letter codes are not activated properly and (2) the information contained within properly activated visual letter codes fails to reach intact graphic motor patterns. Two patients with written spelling agraphia were each given a series of tests aimed at distinguishing between the two possibilities. Results suggest that the written spelling agraphia seen in these two patients arises from different underlying deficits. The results are discussed in terms of the patients' CT scan lesion sites, which were markedly different.

An algebraic approach to Cichelli's perfect hashing

The aim of this paper is to describe a new approach to building minimal and perfect hash functions for a predefined set of keys. Several papers have dealt with this problem and proposed various kinds of functions. This study is based on a function whose address depends both on the letter codes and the letter position in the key, and therefore represents an extension of Cichelli's function. The weights associated with the position are considered to be fixed, and letter code computing is considered to be an interpolation problem. As a result, hash building only requires the solution of an algebraic linear system and then the time complexity is polynomialO(n3).

Processes in handwriting: A case for case

Abstract We present a case study of a right-handed patient with a left parietal lesion of vascular aetiology. His reading and oral spelling were intact, but he displayed a severe deficit in handwriting in which production of lower-case letters was significantly more impaired than production of upper-case letters. We analyse not only the accuracy of his written production of various stimulus materials in various tasks but also its temporal characteristics. Both of these aspects of performance indicate a selective disruption of retrieval of information from physical letter codes.

Identification of pedigrees of hybrid maize (Zea mays L.) cultivars by isozyme electrophoresis and reversed-phase high-performance liquid chromatography

Determination of pedigree by laboratory means can provide an initial and rapid check of hybrid identity in studies designed to compare genotypes. In order to test the accuracy of such determinations, isozymic and chromatographic data were used in an attempt to ascribe pedigrees to 25 hybrids that were identified only by a letter code from a list of 30 inbred lines. The pedigrees of 9 single-cross hybrids were correctly deduced as was the direction in which each cross was made. The pedigrees of 2 hybrids could only be determined ambiguously, however these hybrids were reciprocals and the biochemical data were unable to distinguish between 2 related candidate inbred lines. Pedigrees of 3 hybrids were either incompletely determined or could not be determined from the list of 30 candidate inbred lines and were thus correctly identified as non-Pioneer® brand hybrids. Pedigrees of 9 3-way hybrids could be determined accurately but the pedigrees of 2 non-Pioneer® brand hybrids could not be deduced completely. The ability to correctly ascribe pedigrees of hybrids shows that these data provide a rapid means of determining whether additional field and laboratory tests would be warranted in tests designed to compare genotypic similarity of hybrids.

A speech synthesis system by rule in Japanese

In Japanese, text‐to‐speech systems have to deal with problems of complicated orthography and a writing custom without a clear word separation rule. The system shown here is a tentative one avoiding such troublesome problems, constructed to study the rules in Japanese that are useful for the speech synthesis. In order to obtain natural prosody, as in human text reading, the system should have some mechanism that divides the input sentence into several proper breath groups with pauses based on the analysis of the syntactic structure as a human does. The construction of the system has been accomplished, and it can respond to such a demand. This algorithm was realized as completed software on 2HD diskette, available for the PC‐98 series of personal computer made by NEC. The features of the system are as follows. The input form is word units written in kana letter codes. These units are separated with the space code. No prosody code is necessary except for the punctuation marks. An original parser, based on traditional Japanese grammar, produces the prosody for the synthesized speech.

Gender and hemispheric specialization differences in the learning of Morse code letters

This study investigated changes in hemispheric specialization through five phases in the learning of a novel linguistic code. Naive subjects (N=56) were taught the Morse code equivalents for eight letters. After each phase, a true/false reaction time verification paradigm was used for code-letter combinations presented to the left or right visual field. Reaction times and accuracy were analyzed separately. A significant interaction between sex, responding hand, and visual field was found when reaction times were measured [F(1,52) = 3.95, p =.052]. When accuracy was analyzed, a significant interaction between sex and test phase was found [F(4,216) = 2.80, p <.05]. The results suggest that, in terms of hemispheric specialization, males and females learn a new linguistic code differently. Implications for alternative theories of the development of hemispheric specialization are discussed.

An error analysis of the word‐superiority effect

In this experiment subjects were asked to report the identity of a position‐cued critical letter in a linear array of four letters. There were four types of arrays used: (1) unpronounceable non‐words; (2) pronounceable non‐words; (3) words in which the critical letter was minimally constrained, by the context letters; and (4) words in which the critical letter was maximally constrained by the context letters. A different group of subjects was assigned to each of these four array conditions. All four‐letter stimuli were presented in two parts. A leading array in which the information from two quadrants of a vertical by horizontal division of each letter was presented, and, after intervals of 0, 20, 40, 80, 160, 320, 640 ms and infinity (i.e. no trailing array) a trailing array of the complementary letter parts. Examination of identification errors showed that performance in the word conditions was consistently superior to performance in the non‐word conditions, and the magnitude of this difference (i.e. the word‐superiority effect) increased with increasing stimulus onset asynchrony up to 160 ms and then gradually declined. It was argued that these systematic changes in the size of the word‐superiority effect were suggestive of the presence during encoding of robust word and fragile letter codes. This was consistent with the Interactive Activation Model of Word Perception. However, this model also assumes that all strings of letters are encoded in the same way independent of their linguistic properties, and comparisons of the relative proportions of the types of errors made were not necessarily consistent with this assumption. The identification errors were classified either as ‘intrusion’ (i.e. a report of a letter not in the array), or as ‘ location’ (i.e. a report of a non‐critical or context letter from the array), and an analysis of the proportions of the latter indicated that mislocations contributed more to the total errors in the unpronounceable non‐words than in the other three types of stimuli. This suggested that the non‐words may have been encoded differently.

Vitronectin (S protein) augments the functional activity of monocyte receptors for IgG and complement C3b

An arginine-glycine-aspartic acid sequence (RGD in the single letter code for amino acids) is present in the cell attachment site of both vitronectin and fibronectin. Inasmuch as fibronectin and synthetic peptides containing RGD enhance ingestion of opsonized particles by monocytes, we investigated the effects of vitronectin on phagocytosis by monocytes of sheep erythrocytes bearing IgG (EA) or complement C3b (EC3b). Peripheral blood monocytes were isolated by countercurrent elutriation and allowed to adhere to slides that had been coated with either vitronectin or fibronectin. Next, EA or EC3b were incubated with the adherent monocytes, and phagocytosis was subsequently quantified. Vitronectin caused the same dose dependent increase in phagocytosis as fibronectin. The augmentation of phagocytosis of EA induced by vitronectin could be inhibited by the F(ab')2 fragments of anti- vitronectin IgG but not by preimmune F(ab')2. The maximum phagocytosis of EA induced by vitronectin could not be enhanced by the addition of fibronectin, suggesting that vitronectin and fibronectin act on the same population of monocytes and that the two proteins stimulate the same mechanism through which the enhanced phagocytosis is mediated. Fibronectin and vitronectin caused a tenfold increase in the attachment of EC3b to monocytes, but phagocytosis was augmented minimally. These studies demonstrate that vitronectin modulates interactions between monocytes and opsonized particles.

Vitronectin (S Protein) Augments the Functional Activity of Monocyte Receptors for IgG and Complement C3b

An arginine-glycine-aspartic acid sequence (RGD in the single letter code for amino acids) is present in the cell attachment site of both vitronectin and fibronectin. Inasmuch as fibronectin and synthetic peptides containing RGD enhance ingestion of opsonized particles by monocytes, we investigated the effects of vitronectin on phagocytosis by monocytes of sheep erythrocytes bearing IgG (EA) or complement C3b (EC3b). Peripheral blood monocytes were isolated by countercurrent elutriation and allowed to adhere to slides that had been coated with either vitronectin or fibronectin. Next, EA or EC3b were incubated with the adherent monocytes, and phagocytosis was subsequently quantified. Vitronectin caused the same dose dependent increase in phagocytosis as fibronectin. The augmentation of phagocytosis of EA induced by vitronectin could be inhibited by the F(ab')2 fragments of anti-vitronectin IgG but not by preimmune F(ab')2. The maximum phagocytosis of EA induced by vitronectin could not be enhanced by the addition of fibronectin, suggesting that vitronectin and fibronectin act on the same population of monocytes and that the two proteins stimulate the same mechanism through which the enhanced phagocytosis is mediated. Fibronectin and vitronectin caused a tenfold increase in the attachment of EC3b to monocytes, but phagocytosis was augmented minimally. These studies demonstrate that vitronectin modulates interactions between monocytes and opsonized particles.

Alternative Option Selection Methods in Menu-Driven Computer Programs

In menu-driven computer programs the user is often required to select an option from among several alternatives. The most common response system for this selection is the standard keyboard. Three response selection methods were evaluated: using a key-controlled cursor to point to the desired option, keying a digit to indicate the desired option, and keying a letter that served as a mnemonic device. The speed and errors of selecting options with the alternative methods were studied as a function of (1) the number of the alternative options in the array and (2) familiarity with the program and the options. Results demonstrated the superiority of the meaningful letter code, and the differential and lower effectiveness of cursor and digit as a function of level of practice and number of options. A default selection method that utilizes the practice effect is recommended.

A coding scheme as a basis for the production of customized abstracts

That different kinds of abstracts may be found useful by different users is commonly assumed The purposes of this paper are to outline a method of obtaining independently meaningful abstracts from a single intermediate representation and to consider some preliminary results with software desig ned to implement this method. The implementation involves manual coding: expressions are enclosed in angular brackets, and a number or letter code after each left angular bracket identifies the concept to which the corresponding expression belongs. Some control of sentence order is possible in this implementation and appears to be essential when some ordinary abstracts are coded.

Using Self-Directed Search with Blind Adults

Blind adult members (N = 43; 25 female, 18 male) of a cassette tape-sharing group were administered Holland's Self-Directed Search (SDS) either by cassette tape or with the help of a reader. In both cases, an assistant marked the answers on the SDS form and computed the scale scores. Mean scores and standard deviations were calculated for each of the six Holland personality types for both male and female participants. Results showed that the Social (S) type had the highest means for both men and women. A majority of the women obtained S as the first letter of their Holland code. S was also the most common first letter code for the men. Means were computed for agreement between SDS codes and first occupational daydream codes, using both the Zener-Schnuelle Index and the hexagonal model. A comparison between these means and normative data revealed that blind male agreement scores on the Zener-Schnuelle Index were lower than those for the normative data. Participants’ Holland codes were also compared to codes considered common and rare.

The Miller Disk: An Improvement in the Performance of Manual Reticulocyte Counts

As an important clinical laboratory test, the reticulocyte count suffers from an inherent lack of precision. Accordingly, a method that would increase the degree of precision by incorporating a larger sample size while maintaining cost-effectiveness and convenience was desired. A study was performed to compare the Miller disk method, which employs a visual counting aid, with the standard method of counting. Eight hematology technologists were asked to perform both methods of counting on each of 25 slides using a letter code system to prevent bias. It was found that the Miller disk method showed a significantly greater degree of precision than the standard method of counting (P>.01) because of the increased sample size. The use of the visual counting aid was also found to be more cost-effective in that it decreased technical time incurred, as well as being more convenient.

Resource letter CPE-1: Computers in physics education

This resource letter provides a source of information for physics teachers who wish to use computers in physics education. The letter ‘‘E’’ after a reference indicates a relatively elementary item useful for people just beginning to develop an interest in using computers; the letter ‘‘I’’ denotes intermediate level references for people who have already mastered the specialized vocabulary of computer uses; and the letter ‘‘A’’ denotes advanced material for people who have experience using computers in physics teaching. This letter code does not refer to the level of the physics concepts discussed in any of the articles. An asterisk (*) indicates those articles to be included in an accompanying Reprint Book.

A transform tree code for stationary Gaussian sources

A new tree code is introduced for discrete-time stationary Gaussian sources with hounded, integrable power spectra and the squared-error distortion measure. The codewords in the tree are reconstructions of Karhunen-Loeve transforms of the source words. The branching factor and the number of code letters per branch may vary with level in the tree. A theorem that guarantees the existence of an optimal code for any code rate using such a tree is proved. The proof uses the random coding argument in conjunction with a theorem on survival of a branching process with random environment. A suboptimal but computationally affordable realization of the theorem's coding technique was used for encoding simulations for six autoregressive sources at rates of 1.0, 0.50, 0.25 , and 0.10 bits per source symbol. The average distortion results were generally within 1 dB of the distortion-rate bound but varied widely depending on the source and rate. The results were compared with those for transform quantization simulations for the same sources and rates. The tree code always performed better but only by an average of 0.44 dB all sources and rates. Longer source blocks and more intensive search would certainly improve the performance of the tree codes, but at the expense of extra computation and storage.

The Relative Effectiveness of Alternative Selection Strategies in Menu Driven Computer Programs

The relative efficacy in learning to use different option selection techniques in menu driven programs was evaluated via response time to identical menus, requiring selection of an option out of 2 to 9 alternatives. Negatively accelerating exponential learning functions were obtained for the use of a pointer to note the selected option, keying the number of the option and keying a meaningful letter code (initial) of the option selected. Statistically and practically significant advantage was shown for the letter code, in particular when the number of options was greater than 5. Effects of practice with menu driven programs in general vs. familiarity with a specific program were also demonstrated.

Isolation and characterization of hamster luteinizing hormone.

Hamster pituitaries were collected over an 8-yr period to obtain 3.5 g of dried pituitaries that were submitted to fractionation by extraction with 40% ethanol-acetate buffer at pH 5.5. The 80% acetone precipitate contained all of the gonadotropin activity. This enriched fraction was further purified by Sephadex G-100 and CM-Sephadex chromatography to obtain 4 mg purified hamster LH (haLH). From 1.5 mg haLH, 0.6 mg of the alpha- and beta-subunits were isolated by countercurrent distribution. haLH assayed 0.53 times NIH-LH-S19 by radioligand assay or 0.16 times NIH-LH-S19 by rat Leydig cell steroidogenesis assay. The amino acid N-terminal sequence was: haLH alpha, L-P-D-G-D-F-T-M-Q-G-C-P-; and haLH beta, S-R-G-P-L-R-P-L-C-R-P-I-N*-A-, as represented by the single letter code. The asparagine residue marked by an asterisk was placed by analogy, as this is apparently a carbohydrate-bearing residue. The amino acid compositions of haLH and its subunits are presented. Both subunits are glycoproteins.

Freeze-etch nomenclature for procaryotic bacteria

Abstract A simple nomenclature for the freeze-fractured-etched membranes of procaryotic Gram-positive and Gram-negative micro-organisms is described. With a three letter code, the surface and fracture faces of the bacterial enveloping layers are clearly identified. The first letter defines the fracture face looking towards the bacterial cytoplasm (C) or the exterior (E), the second identifies structures as unfractured surfaces (S) or fractured faces of membranes (F) and the third locates the structure in the bacterial envelope.