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Si wafers were preamorphized by either Si[sub +] or Ge[sub +] ions at temperatures between 5 and 40 °C. The diffusion of low energy (4 keV) B[sub +] implants into the preamorphized Si was studied in order to monitor the flux of interstitials from the end of range (EOR) region toward the surface. Transient enhanced diffusion (TED) in the regrown silicon was observed for all implants. Increasing the implantation temperature of the Si[sub +] implant by as little as 15 °C can result in a marked decrease in the magnitude of the interstitial flux flowing from the EOR region toward the surface. This sensitivity to implant temperature appears to be even greater for Ge[sub +] implants. In order to better understand this effect, detailed transmission electron microscopy (TEM) studies were conducted. As-implanted cross-sectional TEM micrographs indicate a measurable decrease in the thickness of the amorphous layer (up to 300 Å) occurs when the implantation temperature increases from 5 to 40 °C as a result of ion beam induced epitaxial recrystallization. Upon 800 °C annealing, two types of defects are observed in the EOR region: {311} defects and dislocation loops. The {311} defects are unstable and the comparison of secondary ion mass spectroscopy and TEM data for annealed samples indicating the dissolution of these {311} defects is at least one of the sources of interstitials for TED in the regrown Si at 800 °C. The EOR dislocation loops are stable for the annealing conditions used in this study (800 °C for 15 min) and there appears to be an exponential dependence of the TED that occurs in regrown Si on the density of the EOR dislocation loops. [ABSTRACT FROM AUTHOR]

Background: The COVID-19 outbreak brought an unprecedented challenge to the world. Knowledge in the field has been increasing exponentially and the main allergy societies have produced guidance documents for better management of allergic patients during this period. However, few publications so far have provided real-life data from the allergy community concerning allergy practice during the COVID-19 outbreak. Therefore, we proposed an international survey on the management of allergic patients during the current pandemic., Methods: We performed an online survey undertaken to reach out the worldwide allergy community by e-mail and social media. The web-based questionnaire contained 24 questions covering demographic data from the participants, clinical practice during this period, and questions related to the new international classification and coding tools addressed for COVID-19. It was circulated for 8 weeks and had anonymous and volunteer context., Results: Data are presented for 635 participants from 78 countries of all continents. Allergists with long-term professional experience were the main audience. As expected, we received many responses as "I have no data" or "I don't know" to the questions of the survey. However, most with more experience on managing allergic patients during the pandemic agreed that patients suffering from allergic or hypersensitivity conditions have no increased risk of contracting COVID-19 or developing SARS CoV-2. Also, participants mentioned that none of the allergy treatments (inhaled corticosteroids, allergen immunotherapy, biological agents) increased the risk of contracting COVID-19 infection including severe presentations., Conclusion: The data presented are a starting point in the process of getting feedback on all the recommendations provided by the allergy societies; it could also be the basis of new strategies to support health professionals while new COVID-19 specific treatments and vaccines are being explored. The information here presented intends to be helpful to the community but represents a course of action in a highly specific situation due to the state of emergency, and it should be helpful to health systems., Competing Interests: The authors declare that they do not have conflict of interests related to the contents of this article., (© 2021 The Authors.)

Evidence that enables us to identify, assess, and access the small airways in asthma and chronic obstructive pulmonary disease (COPD) has led INTERASMA (Global Asthma Association) and WAO to take a position on the role of the small airways in these diseases. Starting from an extensive literature review, both organizations developed, discussed, and approved the manifesto, which was subsequently approved and endorsed by the chairs of ARIA and GA 2 LEN. The manifesto describes the evidence gathered to date and defines and proposes issues on small airway involvement and management in asthma and COPD with the aim of challenging assumptions, fostering commitment, and bringing about change. The small airways (defined as those with an internal diameter <2 mm) are involved in the pathogenesis of asthma and COPD and are the major determinant of airflow obstruction in these diseases. Various tests are available for the assessment of the small airways, and their results must be integrated to confirm a diagnosis of small airway dysfunction. In asthma and COPD, the small airways play a key role in attempts to achieve disease control and better outcomes. Small-particle inhaled formulations (defined as those that, owing to their size [usually <2 μm], ensure more extensive deposition in the lung periphery than large molecules) have proved beneficial in patients with asthma and COPD, especially those in whom small airway involvement is predominant. Functional and biological tools capable of accurately assessing the lung periphery and more intensive use of currently available tools are necessary. In patients with suspected COPD or asthma, small airway involvement must be assessed using currently available tools. In patients with subotpimal disease control and/or functional or biological signs of disease activity, the role of small airway involvement should be assessed and treatment tailored. Therefore, the choice between large- and small-particle inhaled formulations must reflect the physician's considerations of disease features, phenotype, and response to previous therapy. This article is being co-published in Asthma Research and Practice and the World Allergy Organization Journal.

Dysthymic disorders and major depressions both occur in the elderly. Aggressive but carefully chosen and monitored pharmacologic treatment is indicated in elderly patients with even modest symptoms of depression. Careful attention must be given to the presence of other medical disorders and treatments, physiologic changes of aging, decreased dosage requirements, and side effects. The available antidepressants are compared in terms of their effects on neurotransmitter reuptake mechanisms and the likelihood of producing sedation, anticholinergic effects, and cardiotoxicity. The low anticholinergic potential of desipramine makes it a useful drug in the treatment of geriatric depression.

Previous investigators have reported unfavorable neurologic and developmental outcome of small-for-gestational age (SGA) infants (birth weight less than 1,500 grams born at term or at less than 30 weeks. of gestation. Since obstetrical considerations for the delivery of a SGA fetus often arise between 30 and 38 weeks, the outcome of these survivors becomes a relevant issue. In 1975 and 1976, twenty-eight of 47 such infants survived and 21 were followed sequentially during the first two years. Their birth weight was 1,220 +/- 195 grams (mean +/- S.D.) and the gestation 33.4 +/- 2 weeks. Each SGA infant was paired with a birth weight-matched appropriate-for-gestation (AGA) infant whose birth weight was 1,195 +/- 190 grams and gestation 29 +/- 2 weeks. The weight, length, and head circumference of the SGA infants attained the tenth percentile by 6 to 8 months and were similar to the AGA group. Quarterly neurologic examinations showed similar findings during the first year in the two groups. At 2 years, two SGA (diplegia) and one AGA (hemiplegia) infants were abnormal. The quarterly Bayley scores of the SGA infants were lower during the first 18 months but at 24 months, the two groups had similar scores. The favorable outcome in preterm SGA infants weighing less than 1,500 grams may serve as useful information in making clinical decisions for the management of mothers with suspected intrauterine growth retardation.

Two studies were carried out to determine and compare the effects of several sources of variation on the measurement of corneal thickness using the standard optical pachymeter and three ultrasonic pachymeters. Sources of variation included: intra- and inter-session variation, inter-observer variation, left/right eye variation, and variations due to alternate settings of ultrasonic sound frequencies. It was found that the optical pachymeter had a) two to three times as much intra-session variation as that of the ultrasound pachymeters, b) significant inter-observer variation (P = 0.015), and c) significant differences between left and right eye thickness determinations (P less than 0.005). On the other hand, ultrasonic pachymeters demonstrated a) high reproducibility, b) no inter-observer variation, and c) no left/right eye variation. These results have implications for the use of pachymetry in measuring corneal thickness for radial keratotomy and other refractive surgery.