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Writing medical history papers can be professionally and personally rewarding, but a little overwhelming for novices. This paper offers step-by-step guidelines for the entire process, including developing appropriate topics, finding and using appropriate sources, and writing the paper. Specific reference sources are recommended.
We report the use of an inexpensive, small, and "turn-key" Q-switched 532-nm Nd:YAG laser as a source for nonlinear, direct-write protein microfabrication. In this approach, microJoule pulses (pulse widths, approximately 600 ps) are focused using high numerical aperture optics to submicrometer focal spots, creating instantaneous intensities great enough to promote multiphoton excitation of a photosensitizer and subsequent intermolecular cross-linking of protein molecules. By scanning the femtoliter focal volume through reagent solution, extended protein-based structures can be fabricated with precise, three-dimensional topographies. As with earlier studies using a femtosecond titanium:sapphire laser costing more than 100K, physically robust and chemically responsive microstructures can be fashioned rapidly with feature sizes smaller than 0.5 microm, and cross-linking can be achieved using both biologically benign sensitizers (e.g., flavins) and by using the proteins themselves to sensitize cross-linking. We demonstrate in situ fabrication to corral neurite outgrowth and show the ability to functionalize avidin structures with biotinylated reagents, an approach that enables chemical sensing to be performed in specified microenvironments. Characterization of this inexpensive, low-power source will greatly broaden access to direct-write protein microfabrication.
A new technique for direct-writing of polymer nanostructures on insulating and semiconducting surfaces based on Electrochemical Dip-Pen Nanolithography (E-DPN) is described. The technique is based on electrochemical polymerization of monomers directly underneath the AFM tip. Sub-50 nm poly-3,4-ethylenedioxythiophene lines can be easily created. Such capability to direct-write and pattern polymeric materials with interesting electronic and electrooptical properties at the nanoscale creates a number of opportunities since a large variety of monomers are available.
A new constructive method for the preparation of laterally structured alkylsiloxane monolayers is demonstrated. Laser direct writing has been used to create oxide patterns on H-terminated Si(100) samples under ambient conditions. Depending on the laser power and the writing speed, oxide structures with a lateral resolution below 500 nm are prepared routinely. The patterned samples are suitable as temporary templates for the preparation of laterally structured octadecylsiloxane monolayers. Prior to immersion in an octadecyltrichlorosilane solution, however, hydration of the samples in water is essential to facilitate a selective coating of the oxidized areas. After coating, atomic force microscopy reveals the formation of octadecylsiloxane islands exclusively on top of the oxide lines.
Three-dimensional (3-D) structures with micron-sized features have been fabricated via the direct-write assembly of polyelectrolyte inks. By mixing oppositely charged species under solution conditions that promote polyelectrolyte exchange reactions, we have created concentrated fluids capable of flowing through microscale deposition nozzles. Ink deposition into an alcohol/water coagulation reservoir yielded polyelectrolyte filaments that rapidly solidify to enable three-dimensional patterning of microperiodic structures with self-supporting features. The influence of ink and reservoir chemistry on the phase behavior, rheological properties, and assembly of concentrated polyelectrolyte complexes is reported with an emphasis on the optimal conditions for 3-D writing.
We examined the effect of disclosing to others an attempted or completed rape. Eighty-five undergraduate women who acknowledged attempted or completed rape wrote about their experience and read their narratives. In a 2 x 2 design, we examined the value of writing only factual information versus factual plus emotional information, and reading to oneself versus reading aloud to another woman. Before and 1-month after the task, symptoms of dysphoria, social anxiety and posttraumatic stress disorder were assessed. Greater detail and a moderate level of personalization in the description of the trauma were associated with decreased symptoms of dysphoria and social anxiety. Neither the nature of the writing task nor the presence of another woman predicted degree of symptom reduction.
Psychology students were randomly assigned to a condition in which they had to write for 20 min on 3 days or for 3 min on 1 day a factual description of disclosed traumas, undisclosed traumas, or recent social events. In the case of undisclosed traumatic events, intensive writing about these events showed a beneficial effect on affect and on the affective impact of remembering the event and appraisal. Participants who wrote briefly about an undisclosed traumatic event showed a more negative appraisal. Participants who wrote intensively about a traumatic event and had a dispositional deficit in self-disclosure, measured by a Toronto Alexithymia Scale subscale, showed a positive effect on self-reported measures of affect. Difficulty in describing feelings, an alexythimia dimension, correlated with psychological health problems, emotional inhibition, and a less introspective content of written essays about the emotional events.
The past decade has witnessed intensive research efforts related to the design and fabrication of photonic crystals. These periodically structured dielectric materials can represent the optical analogue of semiconductor crystals, and provide a novel platform for the realization of integrated photonics. Despite intensive efforts, inexpensive fabrication techniques for large-scale three-dimensional photonic crystals of high enough quality, with photonic bandgaps at near-infrared frequencies, and built-in functional elements for telecommunication applications, have been elusive. Direct laser writing by multiphoton polymerization of a photoresist has emerged as a technique for the rapid, cheap and flexible fabrication of nanostructures for photonics. In 1999, so-called layer-by-layer or woodpile photonic crystals were fabricated with a fundamental stop band at 3.9 microm wavelength. In 2002, a corresponding 1.9 microm was achieved, but the important face-centred-cubic (f.c.c.) symmetry was abandoned. Importantly, fundamental stop bands or photonic bandgaps at telecommunication wavelengths have not been demonstrated. In this letter, we report the fabrication--through direct laser writing--and detailed characterization of high-quality large-scale f.c.c. layer-by-layer structures, with fundamental stop bands ranging from 1.3 to 1.7 microm.
Writing treatment that involved repeated copying and recall of target words was implemented with 8 individuals with severe aphasia in order to discern the best candidates for the treatment. Four of the 8 participants had strong positive responses to the copy and recall treatment (CART), relearning spellings for 15 targeted words during 10 to 12 weeks of treatment and up to 5 additional words during a month-long homework-based program. Of the 4 other participants, 3 learned the spellings of some target words but failed to reach criterion, and 1 had a poor treatment outcome. Insights regarding possible factors that limited success were gained by examination of individual responses to treatment as well as performance on the pretreatment assessments of semantic, phonological, and orthographic processes. Among the factors associated with success were (a) consistent, accurate completion of daily homework, (b) a relatively preserved semantic system, (c) the ability to discern words from nonwords, and (d) adequately preserved nonverbal visual problem-solving skills. Aphasia severity and minimal pretreatment spelling abilities did not necessarily limit the response to treatment. Participants with positive treatment outcomes demonstrated improved spelling of target words following repeated copying within a single treatment session, and accurately completed daily writing homework. Thus, pretreatment assessment and stimulability within initial treatment sessions provided indications of likely outcome.
A clinical population of 44 aphasics was rated on the severity of impairment of functional communication in each of four language modalities: verbal comprehension, speech, reading, and writing. Comparisons are made of the severity of impairment in each pair of language modalities for the subjects as a group and for individual subjects. Correlations between severity ratings in each pair of language modalities are also presented. The results indicate that all modalities are impaired to approximately the same degree and that differences between severity ratings across all modalities are small for the large majority of aphasic subjects. Writing is usually the most severely impaired modality. A discussion is presented reviewing the important influences that methodology has on the data obtained and on the inferences which may be drawn about the nature of aphasia as a uni- or multimodality impairment.
A computer-controlled rehabilitation for aphasics with writing impairments is presented. Subjects were asked to type words under dictation. Each time a letter was typed in its correct position, it was displayed on a screen. If the contrary, the error was not displayed, thus avoiding visual reinforcement of false choices. This method of rehabilitation has proved efficient as concerns typewriting. More importantly, some learning transfer to handwriting was observed at the completion of experimental training. The results showed a significant reduction in the number of misspelled words as well as in the erroneous choice and serial ordering of letters. The stability of the observed improvement is discussed in relationship to variables such as the time elapsed since brain damage and the type of writing difficulty.
Primary writing tremor is a task-specific tremor that is considered to be unilateral. We report a 59-year-old man with a 5-year history of a typical primary writing tremor in the right hand who developed similar symptoms in the left hand. Copyright 1998 Lippincott Williams & Wilkins
In left-handedness it is not the right hemisphere which usually dominates, as previously assumed but rather the left, as recent studies show. The development of right- and left-handedness is considered here in the light of the findings of Eccles, who substantiated the hypothesis of a relationship between the brain and a consciousness which is to be seen as basically independent of this organ. Right- and left-handedness are engendered by the interplay between consciousness and certain liasion areas in the brain. When the subject's will dictates a movement, consciousness exercises a strong influence on the impulse pattern of the modules. In genetically conditioned left-handedness it is not primarily motoric, but rather neuronal factors which are responsible for the reversal in the direction of writing and mirror-image script. Left-handed children who produce mirror-handwriting can be retrained to write normally by exercises and by assimilating conscious experience.
When a letter is drawn on the forehead, it is perceived cutaneously as a mirror reversal of the experimenter-defined stimulus. An analogous mirror-reversal phenomenon is found in motor behaviour; eg, writing on the downward-facing horizontal surface of a table. We examined these mirror-reversal phenomena in tasks, performed by 4-year-old and 8-year-old children, involving cutaneous perception and motor-production. The children's tendencies toward mirror reversal in the two tasks varied with the orientation and position of the surface, but were similar to those of sighted and blind adult subjects. In addition, mirror reversal was independent of the left-right indifference often observed in young children in writing or visual-matching tasks. The implications of these findings are discussed in the context of a body schema used to guide sensorimotor functions.
This essay surveys the present state of biographical writing in the history of neurology and neuroscience. Individual lives play a significant role in practitioner-historians' narratives, whereas academic historians tend to be more nonindividualistic and a-biographical. Autobiographies by neurologists and neuroscientists, and particularly autobiographical collections, are problematic as an historical genre. Neurobiographies proper are published with several aims in mind: some are written as literary entertainment, others as contributions to a cultural and social history of the neurosciences. Eulogy, panegyrics and commemoration play a great role in neurobiographical writing. Some biographies, finally, are written to provide role-models for young neuroscientists, thus reviving the classical, Plutarchian biographical tradition. Finally, a recent cooperative biography of Charcot is mentioned as an example of how the biographical genre can help overcome the alleged dichotomy between the historiographies of practitioner-historians and academic historians.
For centuries tedious, often confusing Latin abbreviations have been used in writing prescriptions. A simple four-digit (zip) code is proposed as a new method of writing directions for most drug regimens.
This paper reports a case study of a Cantonese-speaking dysgraphic patient. Among his written errors were phonologically plausible errors that were mostly homophonous or differed only in tone from their target. They occurred not only in writing-to-dictation but also in written naming. Since his lexico-semantic system is hypothesized to be largely preserved, as evidenced by normal performance on non-verbal semantic tests and word-picture matching, the presence of homophone and tonal errors strengthened previous claims about the existence of lexically mediated non-semantic pathway of writing Chinese and access from the phonological output lexicon to the orthographic output lexicon. In addition, his non-character responses, particularly those involving substitution of constituent(s), almost always maintained the configuration of their target. This observation implies that orthographic representations contain not only information on the identity of components but also structural information. The latter may, among other possibilities, take the form of a template indicating the internal organization of the character or specification for position of occurrence for each constituent within the character.
Micrographia (MG), an acquired impairment of writing characterized by diminution of letter size, coupled with slowing and loss of accuracy, is most frequently observed in the course of degenerative disease of basal ganglia, such as Parkinson's Disease. Only a few cases of MG without concomitant extrapyramidal signs have been described, mostly following vascular lesion of the left basal ganglia. In this article we report an isolated pattern of MG following an extensive traumatic cerebral lesion centered in the left basal ganglia. The nature of this impairment is analyzed according to a cognitive model of writing and interpreted as a specific example of peripheral dysgraphia.