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International audience; After decades of observations of solar energetic particles from space-based observatories, relevant questions on particle injection, transport, and acceleration remain open. To address these scientific topics, accurate measurements of the particle properties in the inner heliosphere are needed. In this paper we describe the Energetic Particle Detector (EPD), an instrument suite that is part of the scientific payload aboard the Solar Orbiter mission. Solar Orbiter will approach the Sun as close as 0.28 au and will provide extra-ecliptic measurements beyond ∼30° heliographic latitude during the later stages of the mission. The EPD will measure electrons, protons, and heavy ions with high temporal resolution over a wide energy range, from suprathermal energies up to several hundreds of megaelectronvolts/nucleons. For this purpose, EPD is composed of four units: the SupraThermal Electrons and Protons (STEP), the Electron Proton Telescope (EPT), the Suprathermal Ion Spectrograph (SIS), and the High-Energy Telescope (HET) plus the Instrument Control Unit that serves as power and data interface with the spacecraft. The low-energy population of electrons and ions will be covered by STEP and EPT, while the high-energy range will be measured by HET. Elemental and isotopic ion composition measurements will be performed by SIS and HET, allowing full particle identification from a few kiloelectronvolts up to several hundreds of megaelectronvolts/nucleons. Angular information will be provided by the separate look directions from different sensor heads, on the ecliptic plane along the Parker spiral magnetic field both forward and backwards, and out of the ecliptic plane observing both northern and southern hemispheres. The unparalleled observations of EPD will provide key insights into long-open and crucial questions about the processes that govern energetic particles in the inner heliosphere.

The first orbit of Solar Orbiter provided comprehensive measurements of six corotating interaction regions (CIRs) within 1 au. Five of these CIRs were also observed by ACE at 1 au, allowing for comparisons of the suprathermal ion intensities and spectra at different radial distances. Only subtle modulations of the4He spectral slopes are observed between Solar Orbiter and ACE. Additionally, the radial gradients of 226−320 keV/nuc4He ion intensities between Solar Orbiter and ACE are similar to that of 1.53 MeV H reported by Van Hollebeke et al. (1978, J. Geophys. Res., 83, A10). These observations provide a new addition to the study of the radial dependence of CIR-associated suprathermal ions in the inner heliosphere.

The Solar Orbiter flyby of Venus on 27 December 2020 allowed for an opportunity to measure the suprathermal to energetic ions in the Venusian system over a large range of radial distances to better understand the acceleration processes within the system and provide a characterization of galactic cosmic rays near the planet. Bursty suprathermal ion enhancements (up to ∼10 keV) were observed as far as ∼50RVdowntail. These enhancements are likely related to a combination of acceleration mechanisms in regions of strong turbulence, current sheet crossings, and boundary layer crossings, with a possible instance of ion heating due to ion cyclotron waves within the Venusian tail. Upstream of the planet, suprathermal ions are observed that might be related to pick-up acceleration of photoionized exospheric populations as far as 5RVupstream in the solar wind as has been observed before by missions such as Pioneer Venus Orbiter and Venus Express. Near the closest approach of Solar Orbiter, the Galactic cosmic ray (GCR) count rate was observed to decrease by approximately 5 percent, which is consistent with the amount of sky obscured by the planet, suggesting a negligible abundance of GCR albedo particles at over 2RV. Along with modulation of the GCR population very close to Venus, the Solar Orbiter observations show that the Venusian system, even far from the planet, can be an effective accelerator of ions up to ∼30 keV. This paper is part of a series of the first papers from the Solar Orbiter Venus flyby.

We report observations of five impulsive solar energetic particle (SEP) events observed inside 1 au during the first perihelion pass of the Solar Orbiter mission, which was launched in February 2020. These small events were all reasonably associated with active regions observed from Earth but which had rotated out of view by the time of the Solar Orbiter observations. Even though most of the events were small, their spectral forms,3He content, and association with type III bursts convincingly identifies them as3He-rich impulsive SEP events with properties similar to those previously observed at 1 au. Three of the events showed fast ion rise times, and two of them had long-lasting anisotropies consistent with the Compton-Getting effect.

We report the fabrication and characterization of Kagome hollow-core antiresonant fibers, which combine low attenuation (as measured at ∼30 cm bend diameter) with a wide operating bandwidth and high modal purity. Record low attenuation values are reported: 12.3 dB/km, 13.9 dB/km, and 9.6 dB/km in three different fibers optimized for operation at 1 μm, 1.55 μm, and 2.5 μm, respectively. These fibers are excellent candidates for ultra-high power delivery at key laser wavelengths including 1.064 μm and 2.94 μm, as well as for applications in gas-based sensing and nonlinear optics.

This report describes the use of polymerase chain reaction and DNA in situ hybridization to diagnose Aleutian mink disease parvovirus DNA in various tissue specimens from 2 companion striped skunks. Clinical, laboratory, and microscopic findings also support a clinical diagnosis of Aleutian disease in these mink.

Poultry are increasingly being associated with carriage of multiresistant organisms that may cause disease in humans. Among these organisms are the enterococci, not regarded as a common cause of hospital-acquired infections. The use of antimicrobials for growth promotion in poultry production envronments may facilitate the dissemination of resistance to Enterococcus spp. that have the potential to be clinically significant. To assess descriptively the degree of multiresistant enterococci in the poultry environment of the Delmarva (Delaware-Maryland-Virginia) East Coast region of the USA, litter samples from regional commercial poultry houses and transport container swabs from processing facilities were cultured for Enterococcus spp. Using a microtiter plate adaptation of a conventional biochemical screen, the predominant species identfied were E. faecalis (61.2%), E. faecium (18.6%) and E. gallinarum (2.4%). Resistance to the cephalosporin, macrolide and tetracycline classes of antimicrobials was uniform with broader resistance to penicillin and derivatives present in a majority of E. faecium isolates. High-level streptomycin resistance was evident in close to 30% of all isolates with a majority of E. faecalis variants possessing resistance. High-level gentamicin resistance was detected at a low frequency (2.6%) only within the E. faecalis group with resistance to low-level gentamicin levels present in a majority of both the E. faecalis group and subsets of E. faecium. No unexpected vancomycin resistance was detected. Of particular interest was resistance to the streptogramin quinupristin-dalfopristin (Q-D or Synercid), which was present in 70.4% of E. faecium and E. faecium variants.

Previous studies demonstrated high levels of lipid peroxidation (LP) in the guinea pig adrenal cortex. The present studies were done to determine if adrenal LP activity was influenced by ACTH, the major hormonal regulator of the gland. Guinea pigs were treated with ACTH for 1, 3 or 7 days. In addition, some guinea pigs received ACTH for 7 days and were killed 3 or 7 days later. After treatment, adrenal microsomal fractions were prepared and incubated in vitro with 1 mM ferrous sulfate to initiate LP. ACTH treatment caused a progressive decrease in adrenal LP; activity was almost totally inhibited within 3 days. The inhibitory effects of ACTH on LP were dose-dependent. Following cessation of ACTH treatment, adrenal LP gradually returned toward control levels. Microsomal concentrations of linoleic acid, a major substrate for adrenal LP, were increased by ACTH administration and then also returned to control levels after cessation of treatment. There were no significant changes in adrenal alpha-tocopherol or beta-carotene concentrations resulting from ACTH treatment. The results indicate that ACTH has a role in the regulation of adrenal LP. The actions of ACTH cannot be attributed to an increase in adrenal content of the antioxidants, alpha-tocopherol and beta-carotene, or to a decrease in LP substrate. The actions of ACTH to inhibit LP may contribute to an increase in adrenal hormone production by protecting steroidogenic enzymes from peroxidative degradation.

Because Salmonella spp. can be spread from the production environment to the consumer, strategies are required to control Salmonella. One such intervention involves control of the distribution of the organism in poultry litter. In this regard, we have attempted to determine whether Salmonella spp. are uniformly distributed throughout the litter of commercial poultry houses, or if they are unevenly localized to “hot spots” associated with high surface litter water activity (Aw) and high total moisture levels. Of the 86 houses sampled, 48 (55.8%) were positive for Salmonella spp. using a combination of the drag swab and targeted litter culturing methods. Data are presented that show that elevated Aw and percentage moisture content values representative of targeted litter samples or whole-house moisture status are not statistically predictive of Salmonella contamination, using either drag swab or targeted litter culture results as indicators of contamination. This study suggests that favorable environmental conditions for the growth of Salmonella are unequally dispersed in poultry houses. Because there is not equivalent distribution of salmonellae in the surface litter, the drag swab technique is apparently necessary to adequately survey for Salmonella spp. contamination. The findings further suggest that the development of a methodology to detect areas within houses that possess risk factors favorable for Salmonella growth must also include elevated Aw and percentage moisture content levels. This capability may enable a grower to detect and intervene in these targeted areas with neutralizing procedures, agents, or other substances to provide significant reduction of Salmonella or other poultry-associated food-borne pathogens.

The haemodynamic hypothesis for the pathogenesis of diabetic microangiopathy argues that an initial increase in microvascular blood flow leads to microvascular sclerosis and disturbed autoregulation. Endothelin-1 (ET-1) is an endothelium-derived vasoconstrictor peptide that contributes to basal vascular tone. Impairment of the vasoconstrictor response to ET-1 could result in hyperperfusion and subsequent microvascular damage. The purpose of this study was to determine whether vascular responses to ET-1 are impaired in patients with non-insulin-dependent diabetes mellitus (type 2 diabetes). Ten patients with type 2 diabetes and nine control subjects underwent brachial artery cannulation. Forearm blood flow was measured using strain-gauge venous occlusion plethysmography. ET-1 in three doses of 5, 10, and 20 pmol/min and 0.9% saline placebo was infused in a balanced double-blind randomised manner. Vascular smooth muscle function also was assessed using sodium nitroprusside. Control subjects showed vasoconstriction to ET-1 of 5 (p0.05), 10 (p0.05), and 20 pmol/min (p0.01). In the diabetic group, there was no significant response to ET-1 at 5 pmol/min (p0.05); however, significant vasoconstriction developed at 10 and 20 pmol/min (p0.01). There was a significant difference in response to ET-1 at 5 pmol/min between the diabetic and control groups (p0.05). Responses to sodium nitroprusside were similar in both groups (p0.05). Patients with type 2 diabetes have a blunted vasoconstrictor response to ET-1 despite preserved vascular smooth muscle function.

Summary Aim To evaluate candidal load and carriage of candidal species in 414 insulin-treated diabetes mellitus patients with and without clinical signs of infection. Host factors that could influence candidal load in diabetic patients with oral candidosis were also investigated. Methods Candidal species were recovered from 414 insulin-treated diabetes mellitus patients attending two hospital diabetic clinics, using an oral rinse technique. Results Seventy-seven per cent of diabetic patients carried Candida species in their oral cavity, with C. albicans being the species most frequently isolated. C. dubliniensis was found for the first time in this patient group. Forty per cent of patients colonized with candidal species had no clinical signs of oral candidosis. Where oral candidosis was present, erythematous candidosis was the most common clinical presentation. Candidal load was not associated with age, sex or glycaemic control. However, it was significantly increased in those patients who were tobacco smokers, and non-significantly increased in those patients who wore dentures, or who had clinical signs of oral candidosis. Conclusion The epidemiology of oral candidal carriage and infections in diabetic patients is complex and includes species which have not been previously reported in this group of patients. The development of oral candidosis in insulin-treated diabetes mellitus patients is not the result of a single entity, but rather, a combination of risk factors.

The endothelium plays a pivotal role in modulating the reactivity of vascular smooth muscle through the formation of several vasoactive substances. We examined the effects of endothelium-dependent and independent vasodilators on forearm blood flow in 29 patients with Type 2 (non-insulin-dependent) diabetes mellitus and in 21 control subjects, using venous occlusion plethysmography. Via a brachial artery cannula, increasing amounts of acetylcholine and glyceryl trinitrate were infused in doses of 60, 120, 180 and 240 mmol per min and 3, 6 and 9 nmol per min respectively. NG monomethyl-L-arginine, a stereospecific inhibitor of endothelium derived relaxing factor, was infused to inhibit basal and stimulated release of this dilator substance. Reactive hyperaemic forearm blood flow did not differ between groups. Forearm blood flow responses to each dose of acetylcholine were significantly greater in control than diabetic subjects (p less than 0.01 for all doses). NG monomethyl-L-arginine attenuated forearm blood flow from maximal stimulated values when responses were compared with the natural decline to acetylcholine in forearm flow in both control and diabetic subjects (p less than 0.05 for both groups), but had no effect on basal blood flow responses. Forearm blood flow responses to each dose of glyceryl trinitrate were significantly greater in control than diabetic subjects (p less than 0.05 for all). These data provide evidence for endothelial and smooth muscle dysfunction in diabetes which may have important therapeutic implications.

Detailed measurements at 300 and 77 K have been made of the high-field transport properties of pseudomorphic InAsP/InP modulation-doped heterostructures grown by low-pressure organometallic CVD. The high-field channel velocities are comparable to or better than that of InGaAs/InAlAs heterostructures, and the transport properties of InAs/InP heterostucture suggest that carriers remain confined in the channel even at high fields.

The effects of sustained mesenteric nerve stimulation on intestinal oxygenation were determined in 3- and 35-day-old swine. Studies were conducted in pentobarbital-anesthetized animals during free-flow or constant-flow perfusion. Square-wave stimuli sufficient to induce maximal resistance vessel constriction were applied to postganglionic periarterial mesenteric nerves and each stimulation was sustained until measured variables reached steady state. When vascular resistance data were analyzed without data transformation, autoregulatory escape of intestinal vascular resistance was more complete in 3- than in 35-day-old animals when the escape process was complete; however, expression of these data as escape indexes revealed a similar degree of escape in both age groups. In 35-day-old animals, (a-v)O2 increased during sustained nerve stimulation under free-flow conditions; under constant-flow conditions, (a-v)O2, 86Rb extraction, and capillary permeability-surface area product were lower at completion of the escape process compared with baseline. In 3-day-old swine, these variables remained unchanged from baseline. Intestinal O2 uptake was compromised by sustained nerve stimulation, and this effect was similar in both age groups. We conclude that sustained nerve stimulation reduces intestinal oxygenation to a similar degree in 3- and 35-day-old swine. It is important to note, however, that the response of 3-day-old swine may be dissimilar from that which occurs during immediate postnatal life; indeed, the intestinal hemodynamic response of swine less than or equal to 1 day old should not be extrapolated from the response of 3-day-old animals.

Over the last decade, unusually high losses of colonies have been reported by beekeepers across the USA. Multiple factors such as Varroa destructor, bee viruses, Nosema ceranae, weather, beekeeping practices, nutrition, and pesticides have been shown to contribute to colony losses. Here we describe a large-scale controlled trial, in which different bee pathogens, bee population, and weather conditions across winter were monitored at three locations across the USA. In order to minimize influence of various known contributing factors and their interaction, the hives in the study were not treated with antibiotics or miticides. Additionally, the hives were kept at one location and were not exposed to potential stress factors associated with migration. Our results show that a linear association between load of viruses (DWV or IAPV) in Varroa and bees is present at high Varroa infestation levels (>3 mites per 100 bees). The collection of comprehensive data allowed us to draw a predictive model of colony losses and to show that Varroa destructor, along with bee viruses, mainly DWV replication, contributes to approximately 70% of colony losses. This correlation further supports the claim that insufficient control of the virus-vectoring Varroa mite would result in increased hive loss. The predictive model also indicates that a single factor may not be sufficient to trigger colony losses, whereas a combination of stressors appears to impact hive health., Author Summary Roughly one third of the food supply relies on pollinating insects. The number of colony losses of the domesticated Honey Bee (Apis mellifera) has grown significantly in the past eight years, endangering pollination of crops like almonds. Recent research indicates that colony losses are influenced by a combination of several factors. We conducted an extensive and controlled study that allowed us to look at the contribution of different factors to colony loss. Results helped us build a predictive model showing that a single factor is often insufficient to trigger colony loss. Combination of stressors has shown to have greater impact on hive health; replication of the Deformed Wing Virus, stressful weather conditions, and Varroa destructor comprise the primary identified causes.

Microvascular disease is an important cause of morbidity in diabetes. There is evidence that impaired autoregulation of blood flow is involved in the pathogenesis of diabetic microangiopathy. The vascular endothelium plays a central role in the regulation of vascular tone. Endothelin (ET)-1 is a potent endothelium-derived vasoconstrictor substance that contributes to basal vascular tone. Impaired vasoconstriction in response to endogenous ET could result in hyperperfusion and subsequent microvascular damage. The purpose of our study was to determine whether vascular responses to locally administered ET-1 are impaired in NIDDM. Nine patients with NIDDM and 12 control subjects underwent cannulation of the nondominant brachial artery. Forearm blood flow (FBF) was measured at baseline and during the drug infusion using strain-gauge venous occlusion plethysmography. ET-1 (5 pmol/min) was infused for 60 min at a rate of 1 ml/min. FBF was measured during the first 5 min of the infusion and at 5-min intervals thereafter. Results were expressed as change in FBF from baseline (ml.100 ml−1 · min−1) and were analyzed using repeated measures analysis of variance and Dunnett's test of multiple comparisons. Control subjects showed a gradual onset of vasoconstriction in response to ET-1, which reached maximum at 35 min (1.1 ml.100 ml−1 · min−1; P < 0.01). There was no reduction in FBF in response to ET-1 in the diabetic group. The differences between the diabetic and control groups were significant (P < 0.03). In conclusion, ET-1 infused locally at 5 pmol/min does not cause vasoconstriction in patients with NIDDM.

Objective: Having previously demonstrated release of histamine from mast-cell-deficient rat aorta, the objective of this study was to determine and localize histamine synthe- sis capability in the aorta by detecting histidine decarboxy- lase (HDC), the enzyme that catalyzes histamine formation. Material and methods: Experiments were conducted with nested reverse transcription-polymerase chain reaction (nRT- PCR) to detect HDC mRNA and with immunofluorescence and western blot analysis to detect HDC protein in rat aorta, cultured rat aortic smooth muscle (RASMC) and endothelial cells (RAEC). Results: Gel electrophoresis of nRT-PCR products indicated HDC mRNA in liver, aorta and RASMC but not in RAEC or kidney. Sequence analysis confirmed that the band observed in RASMC was the target HDC amplicon. Immunofluores- cence indicated the presence of HDC protein in RASMC and not in RAEC. Western Blot analysis revealed HDC pro- tein (55 kDa) in liver, aorta, RASMC but not in RAEC or kid- ney. Conclusions: The results of this study are the first to demon- strate the presence of HDC mRNA and protein in rat aorta and more specifically in RASMC, indicative of their capa- bility to synthesize histamine.

The authors report the first investigation of the transport properties of a 2DEG in pseudomorphic InP/InAs/sub x/P/sub 1-x/ modulation-doped heterostructures and the device characteristics of HEMTs (high electron mobility transistors) with an InP/InAs/sub 0.6/P/sub 0.4/ quantum-well channel. The dependence of the low- and high-field transport properties on the arsenic composition (x) has been studied. The Hall mobility for x=0.6 was measured to be 6100 and 52700 cm/sup 2//V-s at 300 and 77 K, respectively. The FETs having a gate length of 0.5 mu m exhibited a maximum external transconductance of 320 mS/mm and a drain saturation current density of 705 mA/mm. The f/sub T/ and f/sub max/ were measured to be 55 and 60 GHz, respectively. The saturation electron velocity was estimated to be 2.1*10/sup 7/ cm/s. The results clearly demonstrate the great potential of these material systems for high-speed applications. >

Endothelin-1 has potent vasoconstrictor and vasopressor actions contributing to basal vascular tone and maintenance of blood pressure acting predominantly through endothelin-A receptors. Endothelin antagonists may be of value in the treatment of hypertension and heart failure. However, the role of endothelin-1 in the regulation of vascular tone and the potential benefits of endothelin antagonists in non-insulin-dependent diabetes mellitus (Type II diabetes) are less clear. Vasoconstriction to exogenous endothelin-1 is impaired in Type II diabetes. The purpose of this study was to determine whether vasoconstriction to endogenous endothelin-1 acting through the endothelin-A receptor is impaired in Type II diabetes. In ten patients with Type II diabetes and nine controls the endothelin-A receptor antagonist BQ123 was infused intra-arterially at 100 nmol/min for 60 min followed by normal saline for 30 min. Forearm blood flow was measured using venous occlusion plethysmography. Control subjects showed gradual onset of vasodilation in response to BQ123 (P0.001). Diabetic subjects, however, showed no significant response (P0.05). There was a significant difference between the diabetic and control groups (P0.05). Blockade of the endothelin-A receptor is associated with impaired vasodilation in Type II diabetes indicating vasoconstriction to endogenous endothelin-1 mediated by the endothelin-A receptor is impaired.

The authors report a novel differential, integrated optical receiver capable of generating symmetric, complementary data signals at the preamplifier stage. The receiver offers superior bandwidth and common mode noise rejection over the conventional transimpedance receiver. A wide-bandwidth receiver implementation in which an InGaAs p-i-n photodiode is DC coupled between a pair of current-source circuits embedded in a GaAs/AlGaAs HBT preamplifier IC is demonstrated. >

The identification of the novel candidal species, C. dubliniensis, from oral swab studies of HIV-seropositive and -seronegative individuals has led to speculation that such a species may also reside in the oral cavity of other patient groups. In this study involvement of the newly described species, C. dubliniensis, was investigated in oral carriage and disease in 414 insulin-using diabetes mellitus patients. Seventy-seven percent of the diabetic patients carried candidal species in the oral cavity. C. albicans was the most commonly identified candidal species. This was followed by C. dubliniensis, which was isolated on 64 occasions. Colonisation with multiple candidal species was common, and C. dubliniensis was present in both carriage and disease states. Seven patients without signs of oral disease had C. dubliniensis isolated as the sole candidal species, while the same species was associated with various forms of oral candidosis in six patients.

This study investigated the influence of the carbon source of the growth medium, strains of Candida albicans and source of epithelial cells, and the influence of smoking and gender, on the adhesion of C. albicans to epithelial cells from insulin-using diabetic patients. Adhesion was determined by an autologous adhesion assay with exfoliated buccal or palatal epithelial cells and one strain of C. albicans isolated from each patient. The type strain CBS 562 was also used. Glucose or sucrose were used as the predominant carbon sources of the growth medium. The autologous strain of C. albicans adhered selectively to the oral mucosa of diabetic patients. Palatal epithelial cells retained significantly more C. albicans in vivo and adhesion was influenced by the availability of sugars in the growth medium and the strain of C. albicans.

The quality of interfaces regrown by organometallic chemical vapor deposition is evaluated from the electrical characteristics of In0.53Ga0.47As/InP p‐n heterojunction diodes. The I‐V curves are undistinguishable from those of junctions obtained by continuous growth, with ideality factors η≊1.1 and no observable contribution from interface recombination in the measured current range. An upper limit of 200 cm/s is obtained for the interface recombination velocity. The results show that high‐quality interfaces can be obtained in spite of prior air exposure. The technique can be used for the realization of regrown heterojunction bipolar transistors.

A novel, electronically integrated, four-channel optical receiver is demonstrated which is designed for electronic channel selection of different wavelength channels in a wavelength-division-multiplexing-based optical network. The receiver consists of four InAlAs-InGaAs metal-semiconductor-metal (MSM) photodetectors that can be independently switched on or off electronically by a digital signal. An optical extinction ratio of 20 dB for the MSM detector was observed. The sensitivity of this optoelectronic integrated circuit receiver is -25.2 dBm at 1.2 Gb/s data rate. >

To evaluate candidal load and carriage of candidal species in 414 insulin-treated diabetes mellitus patients with and without clinical signs of infection. Host factors that could influence candidal load in diabetic patients with oral candidosis were also investigated.Candidal species were recovered from 414 insulin-treated diabetes mellitus patients attending two hospital diabetic clinics, using an oral rinse technique.Seventy-seven per cent of diabetic patients carried Candida species in their oral cavity, with C. albicans being the species most frequently isolated. C. dubliniensis was found for the first time in this patient group. Forty per cent of patients colonized with candidal species had no clinical signs of oral candidosis. Where oral candidosis was present, erythematous candidosis was the most common clinical presentation. Candidal load was not associated with age, sex or glycaemic control. However, it was significantly increased in those patients who were tobacco smokers, and non-significantly increased in those patients who wore dentures, or who had clinical signs of oral candidosis.The epidemiology of oral candidal carriage and infections in diabetic patients is complex and includes species which have not been previously reported in this group of patients. The development of oral candidosis in insulin-treated diabetes mellitus patients is not the result of a single entity, but rather, a combination of risk factors.

We have fabricated a front‐surface‐emitting laser diode (FSELD) using a technique which relies on a double ion implant of oxygen and beryllium. The laser had a low operating voltage at the lasing threshold, a low series resistance, and a relatively small threshold current of 6 mA for a 25‐μm‐diam device. The lasing wavelength was 971 nm and the spectral width above threshold was 5 A. Since the light comes from the front surface of the wafer, the fabrication technique described here for realizing a FSELD can be used for the fabrication of vertical‐cavity visible surface‐emitting lasers.

To establish criteria to differentiate two patterns of vomiting and to identify the predominant diagnoses for each group.All children 2 to 18 years of age referred to a pediatric gastroenterology service who presented with recurrent vomiting (three episodes of vomiting within a 3-month period) as a primary complaint from 1985 to 1991 were retrospectively reviewed (n = 106). The vomiting pattern (emeses per hour and episodes per month), diagnostic studies, and therapeutic responses were compared by Mann-Whitney U and chi-squared tests.Based on the criteria of peak intensity (four or more emeses per hour) and frequency (nine or fewer episodes per month), two subgroups were differentiated: chilcren with a cyclic pattern (n = 34), who vomited at a higher peak intensity (12.6 +/- 1.6 vs 1.5 +/- 0.1 emeses per hour) but at a lower frequency (1.9 +/- 4.8 vs 36.6 +/-0.3 episodes per month) than those with a chronic pattern (n = 72). Among children with a cyclic patern, nongastrointestinal (65%) causes, especially peptic and infectiouus disorders, predominated over nongastrointestinal ones (10%).On the basis of quantitative historical criteria, children with recurrent vomiting can be classified into two subgroups that seem to be clinically and etiologically distinct. Abdominal migraine was the dominant diagnosis in those with cyclic vomiting, whereas peptic and infectious gastrointestinal disorders predominated in those with chronic vomiting. This differentiation between cyclic and chronic patterns of vomiting may be a useful diagnostic clue to the clinician.

The advantage of using a simple flat file program is its simplicity and flexibility. The user has control over screen and report design; creating a database that meets the specific needs of a single department is easy and inexpensive. On the other hand, flat file programs have limitations. The main problem with QA is the need to duplicate data in two or more files. Other limitations are a result of the menu-oriented system, which requires compromises in report formatting and other areas. Database management systems are improving rapidly. Relational databases are becoming easier to use and can overcome many of the limitations of a flat file system. Flat file systems are becoming more enhanced and are beginning to look relational. Developing a system using a simple flat file approach allows the novice to identify and use information without conceptualizing a relational structure. Information can be entered and used quickly, with a better understanding of how everything works. Fewer things can go wrong and need fixing. Keeping your systems simple and following our other guidelines will allow you to use the computer as a tool to increase productivity.

Decreased release of nitric oxide from damaged endothelium is responsible for the impaired endothelium-dependent vasodilator responses found in animal models of vascular disease. Dietary supplementation with fish oils has been shown to augment endothelium-dependent relaxations, principally by improving the release of nitric oxide from injured endothelium. Using forearm venous occlusion plethysmography we studied vascular responses to 60, 120, 180 and 240 nmol/min of acetylcholine (an endothelium-dependent vasodilator) and 3, 6 and 9 nmol/min of glyceryl trinitrate (an endothelium-independent vasodilator) infused into the brachial artery in 23 patients with Type 2 (non-insulin-dependent) diabetes mellitus. NG monomethyl-L-arginine was employed to inhibit stimulated and basal release of nitric oxide from the endothelium. On completion of the baseline studies patients randomly received either fish oil or matching olive oil capsules in a double-blind crossover fashion for 6 weeks followed by a 6-week washout period and a final 6-week treatment phase. Studies, identical to the initial baseline studies, were performed at the end of the active treatment periods at 6 and 18 weeks. Fish oil supplementation significantly improved forearm blood flow responses to each dose of acetylcholine when compared to the vasodilator responses recorded at baseline and after olive oil administration (p < 0.01). Neither fish oil nor olive oil supplementation produced any significant changes in forearm blood flow to the incremental infusions of glyceryl trinitrate when compared with responses recorded during the baseline studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Feces-stained eggshells, diarrhea, and typhlitis were identified in two commercial laying flocks in Ohio. Hens with diarrhea had spirochetes in cecal lumina and crypts. On culture, the spirochetes were motile and non-hemolytic, did not produce indole, had 12 to 15 axial filaments, were 9.2 to 11.7 microns in length and 240 to 370 nm in diameter, and had a wavelength of 5.1 to 6.5 microns on transmission electron microscopy.

We describe a study made at two pediatric centers to test experimental lancets for blood collection by skin puncture of infants' heels or fingers. Our primary goal is to decrease the hazard of osseous injury while collecting adequate blood, by using three lancet widths at a constant length of 1.0 mm. The three widths used were 1.0, 1.25, and 1.5 mm. When success at skin puncture was defined rigidly on the basis of the blood volume obtained, the data show that success was related neither to the lancets' dimensions as tested nor to the age of the child, but rather to the phlebotomist's skill and experience, which improved with time.

Necrotizing typhlocolitis was diagnosed in 13 juvenile common rheas (Rhea americana) from three separate of geographically isolated Ohio flocks, with mortality ranging from 25% to 80%. At postmortem examination, a diphtheritic membrane covered ulcerated cecal mucosa. Histologically, cecal sections showed necrosis and granulomatous-to-suppurative inflammation that extended into the submucosa and often surrounded large eosinophilic colonies of bacteria. Warthin-Starry staining showed these colonies to be composed of entangled spirochetes that invaded the submucosa and frequently were present transmurally. Similar organisms were identified by Warthin-Starry staining in the cecum of a juvenile rhea from a fourth flock that histologically had mild lymphocytic typhlitis. Scanning and transmission electron microscopy demonstrated the presence of a spirochete in the ceca. Anaerobic culture yielded a gram-negative, beta-hemolytic spirochete. Coccidia, histomonads, and Salmonella spp. were consistently absent.

The routing of central office (CO) traffic in a survivable ring network requires system bit rates at or beyond OC-48 (2.5 Gbit/s) to accommodate a large number of COs in a fast growing SONET network. A recent Bellcore study suggests increasing the system operation bit rate to OC-96 (5 Gbit/s) or OC-192 (10 Gbit/s) for potential cost savings, ease of maintenance, and system survivability.1 The design of high-speed optical receivers for SONET lightwave systems of 2.5-10 Gbit/s is a challenging task. Ideally, the receiver should be highly integrated, with differential operation throughout to minimize common-mode noise and power supply fluctuations, and reduce the sensitivity penalty due to parasitic feedbacks.

Fatigue is a very common symptom among cancer patients. It is crucial to diagnose those patients for whom the fatigue is a symptom of depression, and to treat them appropriately. The key to providing complete and satisfying care is to identify and address the psychologic, social, and medical vulnerabilities of each cancer patient. No one is in a better position to accomplish that than the primary physician.

Dual-energy x-ray bone densitometry was used to study the lumbar vertebral bone mass in 218 healthy children (134 girls and 84 boys) aged 1-19 years. Vertebral bone mass increased with weight, age, and pubertal Tanner stage. Results of multiple regression analyses showed that Tanner stage and weight were the best predictive indicators of bone mass and bone mineral density. The influences of age, sex, race, physical activity, and diet were not significant when Tanner stage and weight were controlled. Two tables of predictive intervals for lumbar vertebral bone mineral density in healthy children (one based on Tanner stage and weight; the other, on age and weight) are presented. With normative data now available for use with this precise technique, clinicians can better detect abnormal bone mineral density in children and evaluate changes in mineralization over time.