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1.
PLoS One ; 15(4): e0223304, 2020.
Article in English | MEDLINE | ID: mdl-32302310

ABSTRACT

INTRODUCTION: Sea-level rise is a consequence of climate change that can impact the ecological and physiological changes of coastal, ground-dwelling species. Sea-level rise has a potential to inundate birds, rodents, spiders, and insects that live on the ground in coastal areas. Yet, there is still much to be learned concerning the specifics of these impacts. The red imported fire ant Solenopsis invicta (Buren) excavates soil for its home and is capable of surviving flooding. Because of their ground-dwelling life history and rapid reproduction, fire ants make an ideal model for discovery and prediction of changes that may be due to sea-level rise. There are up to 500,000 individuals in a colony, and these invasive ants naturally have a painful sting. However, observations suggest that colonies of fire ants that dwell in tidally-influenced areas are more aggressive with more frequent stings and more venom injected per sting (behavioral and physiological changes) than those located inland. This may be an adaption to sea-level rise. Therefore, the objective of this study is to elucidate differences in inland and coastal defensiveness via micro-dissection and comparison of head width, head length, stinger length, and venom sac volume. But first because fire ants' ability to raft on brackish tidal water is unknown, it had to be determined if fire ants could indeed raft in brackish water and examine the behavior differences between those flooded with freshwater vs. saltwater. METHODS: To test the coastal-aggression hypothesis, inland colonies and coastal colonies, which experience relatively greater amounts of flooding, specifically regular tidal and windblown water and oscillations (i.e. El Nino Southern Oscillation) from the Gulf of Mexico, were collected. To mimic sea-level rise, the colonies were flooded in salinities that correspond to both their collection site and conditions found in a variety of locales and situations (such as storm surge from a tropical storm). Individual ants were immediately taken from each colony for dissection before flooding, 1-hour into flooding, and 24-hours into flooding. RESULTS AND DISCUSSION: Fire ants use their venom to defend themselves and to communicate alarm or aggression. Dissections and measurement of heads, venom sacs, and stingers revealed both coastal and inland colonies experience an increase in venom sac volume after 24 hours; in fact coastal colonies increased their venom volume by 75% after 24 h of flooding Whether this venom sac enlargement is due to diffusion of water or venom sac production is unknown. These ground-dwelling ants exhibit physiological and behavioral adaptations to ongoing sea-level rise possibly indicating that they are responding to increased flooding. Fire ants will raft on high-salinity water; and sea-level rise may cause stings by flooded ants to be more severe because of increased venom volume.


Subject(s)
Adaptation, Physiological , Ants/physiology , Sea Level Rise , Animals , Arthropod Venoms/metabolism , Behavior, Animal , Ecosystem
2.
J Hunger Environ Nutr ; 14(5): 709-724, 2019.
Article in English | MEDLINE | ID: mdl-31749895

ABSTRACT

Studies examining the impact of food insecurity on metabolic markers are limited, specifically in Hispanic youth. This study was a cross-sectional analysis of 218 3rd-5th grade students (83% Hispanic and 49% male). Anthropometrics, blood glucose, insulin, and lipids via fasting blood draw, dietary intake via Block screener, and a 5-item food security scale were collected. HOMA-Insulin Resistance was calculated. Multivariate analyses of covariance were used to examine differences in glucose and insulin indices, adiposity, metabolic and dietary intake variables between categories of food security. Food secure children had greater glycemic control and decreased insulin resistance compared to food insecure children.

3.
Curr Dev Nutr ; 3(8): nzz080, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31414072

ABSTRACT

BACKGROUND: The purpose of this study was to expand the School Physical Activity and Nutrition questionnaire to include a greater variety of vegetables and to evaluate the relative validity and reliability of these revised items. OBJECTIVES: This study utilized 2 convenience samples of third to fifth graders for an analysis: validity (n = 70) and reliability (n = 76). Validity was assessed by comparing questionnaire items with vegetable intake reported from a 24-hour dietary recall covering the same reference period. Reliability estimates were assessed via same-day test-retest. RESULTS: Agreement correlations ranged from 0.35 to 0.71. Kappa statistics varied from 0.16 to 0.66. Percentage agreements ranged from 57% to 87%. Test-retest Spearman coefficients were greater than 0.50 for 6 items, weighted Kappa values were greater than 0.40 for all 7 items, and percentage agreement exceeded 75% for 5 items. CONCLUSIONS: Results suggest that the questionnaire is a valid and reliable measure of the previous day's vegetable intake in third- to fifth-grade students. This trial was registered at ClinicalTrials.gov as NCT02668744.

4.
Clin Obes ; 8(4): 236-243, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29896938

ABSTRACT

Research examining the impact of artificial sweetened beverages (ASBs) on obesity and metabolic diseases in adolescents is limited. The overall goal is to examine the longitudinal effects of ASBs on changes in adiposity and metabolic parameters in Hispanic adolescents. Longitudinal cohort with 98 Hispanics (12-18 years) who were overweight or had obesity with the following data at baseline and 1-year later: anthropometrics, diet (24-h recalls), body composition (DXA), glucose and insulin dynamics (oral glucose tolerance and frequently sampled intravenous glucose tolerance test) and fasting lipids. Repeated measures analyses of covariance assessed changes over time between control (no ASBs at either visit), ASB initiators (no ASBs at baseline/ASBs at 1-year) and chronic ASB consumers (ASBs at both visits). ASB initiators (n = 14) and chronic ASB consumers (n = 9) compared to control (n = 75) had higher total body fat at baseline and 1-year (P = 0.05 for group effect). Chronic ASB consumers had a 6% increase in haemoglobin A1c, 34% increase in energy intake (kcal d-1 ) and 39% increase in carbohydrate intake (g d-1 ) over time, while control and ASB initiators maintained (P < 0.05 for group-by-time interactions). These results do not support promoting ASBs as a strategy for adiposity loss or to improve metabolic health.


Subject(s)
Adiposity , Beverages/analysis , Glycated Hemoglobin/metabolism , Obesity/metabolism , Sweetening Agents/metabolism , Adolescent , Beverages/adverse effects , Blood Glucose/metabolism , Child , Cohort Studies , Energy Intake , Female , Hispanic or Latino/statistics & numerical data , Humans , Insulin/metabolism , Male , Obesity/etiology , Obesity/physiopathology , Sweetening Agents/adverse effects
5.
AJR Am J Roentgenol ; 161(1): 33-6, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8517316

ABSTRACT

OBJECTIVE: The symmetric distribution of pulmonary vascular congestion and edema caused by left ventricular heart failure associated with severe mitral regurgitation as seen on chest radiographs is well known. To our knowledge, only eight cases have been reported in which congestion and edema were confined to one lung or a portion of one lung. The purpose of this study was to determine the prevalence of asymmetric findings in these patients. MATERIALS AND METHODS: Three radiologists retrospectively and independently reviewed the plain chest radiographs of 131 patients with severe mitral regurgitation admitted to our institution during a 3-year period. Radiographs showing asymmetric vascular congestion or pulmonary edema were identified. Clinical records of these patients were studied to exclude other causes of pulmonary disease. RESULTS: Radiographic signs of vascular congestion and edema were present in 117 (89%) of the 131 patients. In 12 (9%) of 131 patients, these findings were localized or predominant in the upper lobe of the right lung. None of the patients had predominantly left-sided involvement. CONCLUSION: Pulmonary vascular congestion and edema involving predominantly the upper lobe of the right lung in patients with severe mitral regurgitation occurs more frequently than previously thought. This information is useful in the differential diagnosis of right upper lobe abnormalities, such as pneumonia.


Subject(s)
Mitral Valve Insufficiency/complications , Pulmonary Edema/etiology , Aged , Female , Humans , Lung/diagnostic imaging , Lung/pathology , Male , Middle Aged , Pulmonary Edema/diagnostic imaging , Pulmonary Edema/pathology , Radiography , Retrospective Studies
6.
J Psychoactive Drugs ; 24(3): 273-6, 1992.
Article in English | MEDLINE | ID: mdl-1432406

ABSTRACT

Cocaethylene is a psychoactive ethyl homologue of cocaine, and is formed exclusively during the coadministration of cocaine and alcohol. Not a natural alkaloid of the coca leaf, cocaethylene can be identified in the urine, blood, hair, and neurological and liver tissue samples of individuals who have consumed both cocaine and alcohol. With a pharmacologic profile similar to cocaine, it can block the dopamine transporter on dopaminergic presynaptic nerve terminals in the brain. It increases dopamine synaptic content, provoking enhanced postsynaptic receptor stimulation, resulting in euphoria, reinforcement, and self-administration. Equipotent to cocaine with regard to dopamine transporter affinity, cocaethylene appears to be far less potent than cocaine with regard to serotonin transporter binding. Lacking the serotonergic-related inhibitory mechanism, cocaethylene appears to be more euphorigenic and rewarding than cocaine. Synthesized and administered cocaethylene has a behavioral stimulation profile similar to cocaine. Cocaethylene has been shown to be less potent and equipotent to cocaine, and alcohol plus cocaine produces more stimulatory locomotor behavior in mice than either drug alone. Equipotent to cocaine with regard to primate reinforcement and self-administration, cocaethylene can substitute for cocaine in drug discrimination studies, and can produce stimulation of operant conditioning in rats. With regard to lethality, cocaethylene has been shown to be more potent than cocaine in mice and rats. The combination of cocaine and alcohol appears to exert more cardiovascular toxicity than either drug alone in humans. Alcohol appears to potentiate cocaine hepatotoxicity in both humans and mice.


Subject(s)
Cocaine/analogs & derivatives , Neurotransmitter Uptake Inhibitors/pharmacology , Animals , Cocaine/analysis , Cocaine/pharmacology , Cocaine/toxicity , Dopamine/physiology , Humans , Lethal Dose 50 , Neurotransmitter Uptake Inhibitors/analysis , Neurotransmitter Uptake Inhibitors/toxicity , Psychomotor Performance/drug effects , Reinforcement, Psychology
7.
J Am Board Fam Pract ; 5(2): 167-75, 1992.
Article in English | MEDLINE | ID: mdl-1575069

ABSTRACT

BACKGROUND: Primary care physicians prescribe benzodiazepines for the treatment of anxiety. Although most patients use the benzodiazepines appropriately, some patients experience benzodiazepine abuse, addiction, or physical dependence, each one of which is a distinct syndrome. Benzodiazepine dependence, which relates to the development of tolerance and an abstinence syndrome, can be produced by three disparate benzodiazepine use patterns. These distinct benzodiazepine use patterns can in turn create distinct withdrawal syndromes. High-dose benzodiazepine use between 1 and 6 months can produce an acute sedative-hypnotic withdrawal syndrome. In contrast, low-dose therapeutic range benzodiazepine use longer than 6 months can produce a prolonged, subacute low-dose benzodiazepine withdrawal syndrome. Daily, high-dose benzodiazepine use for more than 6 months can cause a combination of an acute high-dose benzodiazepine withdrawal and a prolonged, subacute low-dose withdrawal syndrome. In addition, patients may experience syndrome reemergence. METHODS: A literature search was conducted using the medical subject headings benzodiazepines, substance abuse, substance dependence, substance withdrawal syndrome, and benzodiazepines adverse effects. The years 1970 to the present were reviewed. RESULTS AND CONCLUSIONS: Medical management for acute benzodiazepine withdrawal includes the graded reduction of the current benzodiazepine dosage, substitution of a long-acting benzodiazepine, and phenobarbital substitution. However, the medical management of benzodiazepine dependence does not constitute treatment of benzodiazepine addiction. Primary care physicians can accept complete, moderate, or limited medical responsibility regarding patients with substance use disorders. However, all physicians should provide diagnostic and referral services.


Subject(s)
Benzodiazepines , Family Practice/methods , Substance Withdrawal Syndrome/therapy , Substance-Related Disorders/therapy , Clinical Protocols/standards , Humans , Long-Term Care , Phenobarbital/administration & dosage , Phenobarbital/therapeutic use , Physician's Role , Severity of Illness Index , Substance Withdrawal Syndrome/drug therapy , Substance-Related Disorders/classification , Substance-Related Disorders/drug therapy , Therapeutic Equivalency
8.
J Am Board Fam Pract ; 4(6): 447-56, 1991.
Article in English | MEDLINE | ID: mdl-1767697

ABSTRACT

Primary care physicians routinely treat patients with various anxiety disorders. These patients may have a substance use disorder or may be at high risk for abuse or addiction. Routine treatment of anxiety disorders with psychoactive drugs is successful in many patients, but it can lead to iatrogenic dependence in high-risk patients. This article describes addiction risk factors, drug pharmacodynamics, environment and environmental cues, and genetics. With these addiction risk factors in mind, the physician can apply a stepwise treatment protocol described in three progressive levels: conservative, nonpharmacological approaches; nonpsychoactive pharmacotherapy; and psychoactive pharmacotherapy. In addition, proper prescribing practices for high-risk patients are described in terms of diagnosis, dosage, duration, discontinuation, dependence, and documentation.


Subject(s)
Anxiety Disorders/therapy , Family Practice/methods , Substance-Related Disorders/therapy , Anxiety Disorders/complications , Anxiety Disorders/epidemiology , Clinical Protocols/standards , Humans , Psychotherapy , Psychotropic Drugs/therapeutic use , Risk Factors , Substance-Related Disorders/complications , Substance-Related Disorders/epidemiology
9.
J Psychoactive Drugs ; 23(4): 397-416, 1991.
Article in English | MEDLINE | ID: mdl-1813612

ABSTRACT

Attending physicians routinely encounter patients with signs and symptoms of anxiety and mood disorders as well as psychoactive substance use and psychoactive substance-induced organic mental disorders. These symptoms may represent either primary disorders or pathology that is secondary to other disorders. This article describes some of the relationships between substance use disorders and symptoms of anxiety and depressive disorders. In addition, some patients with these disorders may have a concurrent substance use disorder or be at high risk for developing one. Routine treatment of anxiety disorders with psychoactive drugs can be successful in many patients but may lead to iatrogenic dependence in high-risk patients. Prescribing for high-risk patients should include a stepwise treatment protocol having three progressive levels: (1) conservative, nonpharmacological approaches; (2) nonpsychoactive pharmacotherapy, including the use of anxioselective agents, such as buspirone; and (3) psychoactive pharmacotherapy, such as the use of benzodiazepines. Proper prescribing practices for high-risk patients are described in terms of diagnosis, dosage, duration, discontinuation, dependence, and documentation.


Subject(s)
Anxiety/therapy , Depressive Disorder/therapy , Drug Prescriptions , Substance-Related Disorders/therapy , Anxiety/diagnosis , Anxiety/drug therapy , Depressive Disorder/diagnosis , Depressive Disorder/drug therapy , Drug Utilization , Humans , Substance-Related Disorders/diagnosis , Substance-Related Disorders/drug therapy
10.
J Am Board Fam Pract ; 4(1): 47-53, 1991.
Article in English | MEDLINE | ID: mdl-1996512

ABSTRACT

Primary care physicians encounter many patients with primary and secondary anxiety and substance use problems. Some patients have a dual diagnosis of both an anxiety and a substance use disorder. Symptoms may be overdiagnosed, underdiagnosed, and misdiagnosed. This article provides the primary care physician with an overview of the relation between psychoactive substance use disorders and anxiety symptoms. Also described are drug use patterns and diagnostic criteria for psychoactive substance use disorders. A model for understanding the role of anxiety symptoms during drug use is provided.


Subject(s)
Anxiety Disorders/diagnosis , Family Practice , Substance-Related Disorders/diagnosis , Anxiety Disorders/psychology , Decision Trees , Diagnosis, Differential , Humans , Substance-Related Disorders/etiology , Substance-Related Disorders/psychology
11.
Appl Opt ; 30(9): 1052-61, 1991 Mar 20.
Article in English | MEDLINE | ID: mdl-20582105

ABSTRACT

This paper describes the testing of small sized systems and their components that use power-by-light (PBL) to transfer energy across a barrier. The PBL systems used improved high power laser diodes, large numerical aperture fibers, improved high efficient, high power solar cells, and low input-to-high output voltage dc-dc converters. The laser diodes emitted up to 3.6 W continuously by converting approximately 40% of its electrical power to light power into fibers that transmitted up to 92% of its incident energy flux. The specially fabricated solar cell converted 46% of its incident light power to electrical power at a fill factor of 89%. The most efficient 100- and 220-mJ PBL systems charged capacitors in 0.64 and 0.8 s for a total system efficiency of 3.4 and 5.5%. Expected improvements could yield system efficiencies of 12%.

12.
Appl Opt ; 30(18): 2514-26, 1991 Jun 20.
Article in English | MEDLINE | ID: mdl-20700239

ABSTRACT

This paper describes the characteristics of optical couplers with high power laser diodes as sources. The couplers investigated include gradient-index (GRIN) lenses manufactured by Nippon Sheet Glass, a plano-convex lens, a prism, optical fibers manufactured by Ensign-Bickford and Nippon Sheet Glass, and fiber optic stub manufacture by Spec Tran. The characteristics measured included: (1) GRIN lens transmission of up to 97%, fiber transmission of up to 90%, plano-convex lens transmission of up to 92%; (2) intensity distribution contours and profiles of the beam transmitted through GRIN lenses and optical fibers; (3) the beam dimensions of a collimating system; and (4) the divergence of optical fibers of varying lengths. Spectra Diode Laboratory and McDonnell Astronautics Company/Opto Electronics Center manufactured the laser diodes sources that emitted up to 3.6 W.

13.
J Psychiatr Res ; 24 Suppl 2: 145-56, 1990.
Article in English | MEDLINE | ID: mdl-1980693

ABSTRACT

Benzodiazepines are commonly encountered in both psychiatric and chemical dependency treatment settings. However, in the chemical dependency setting, benzodiazepines are most frequently used as secondary drugs of abuse, and are most often found within a polydrug use pattern. Benzodiazepine use by the drug-abusing population consists of the combined use of benzodiazepines with other psychoactive drugs. They are used to medicate cocaine toxicity, as a secondary or tertiary drug to boost the effects of alcohol or heroin, and by those who have developed tolerance and dependence to sedative-hypnotic drugs. The presence of an anxiety disorder, a family history of addiction, or benzodiazepine polydrug use will significantly affect the type of withdrawal a patient will experience and its treatment course. Medical procedures accepted for benzodiazepine discontinuation include (1) graded reduction; (2) substitution of a long-acting benzodiazepine; and (3) phenobarbital substitution.


Subject(s)
Anti-Anxiety Agents , Illicit Drugs , Substance Withdrawal Syndrome/rehabilitation , Substance-Related Disorders/rehabilitation , Anti-Anxiety Agents/adverse effects , Benzodiazepines , Dose-Response Relationship, Drug , Drug Administration Schedule , Humans , Phenobarbital/administration & dosage , Propranolol/administration & dosage
16.
Appl Opt ; 17(4): 635-41, 1978 Feb 15.
Article in English | MEDLINE | ID: mdl-20197840

ABSTRACT

Exploding PbS film Q-switches in a Nd(3+) glass laser produce approximately 40-nsec. giant pulses. This investigation characterizes the laser giant pulse energy, over-all efficiency and ratio of giant pulse energy to total output energy as functions of flashlamp input energy, PbS film reflectivity, output mirror reflectivity, and flashlamp pulse width for both an apertured and unapertured laser. The laser emits giant pulses which contain 0.88 J and 1.8 J of energy, at an over-all efficiency of 0.086% and 0.21% for an apertured and unapertured laser, respectively, and ratios of giant pulse energy to total output energy approaching 100%. This investigation has illustrated that a laser Q-switched by a PbS exploding film can emit more energy, more efficiently, than the same laser Q-switched by a conventional Pockels cell. It is suspected that PbS is not the most efficient material; however, other material could be tested in a similar manner to determine a more optimum material.

17.
Appl Opt ; 17(11): 1764-70, 1978 Jun 01.
Article in English | MEDLINE | ID: mdl-20198066

ABSTRACT

Five bleaching techniques for Agfa Gevaert Scientia 10E75 high-resolution plates were evaluated to determine resultant diffraction efficiency and SNR for identically recorded single-exposure holograms. We determined the optimum recording conditions for both single- and multiple-exposure bleached holograms using a cupric bromide bleach, judged to be the "best bleach." Data are presented for diffraction efficiency, SNR, and resolution of diffuse and focused-image holograms for both single- and multiple-exposure holograms, using a 1951 Air Force resolution chart as the object. Bleaching improved the diffraction efficiency of both types of holograms by up to 3 orders of magnitude. The SNR of diffuse holograms is degraded by bleaching, but that of the focused-image holograms is improved, while the resolution of both types is not affected by bleaching. Bleached multiple-exposure holograms are similar in response to single-exposure holograms except that their diffraction efficiencies are lower. The diffraction efficiency of bleached holograms decreases with age.

18.
Appl Opt ; 14(9): 2260-6, 1975 Sep 01.
Article in English | MEDLINE | ID: mdl-20154997

ABSTRACT

The holographic characteristics of Agfa-Gevaert Scientia 10E75 have been examined for multiple exposures. They include not only diffraction efficiency, but SNR and resolution as functions of number of exposures, time of development, and/or input modulation (rho'). The maximum diffraction efficiency, occurring at a density of 0.7, was observed to increase with increasing development time and decrease as the number of exposures increased. An approximately 10% decrease in maximum diffraction efficiency was observed for each successive reconstructed image of a multiple exposure hologram. Reconstructed noise was found to be fairly well represented by grain-noise considerations only for the region 0.1 < rho' < 0.4. Elsewhere noise is considerably different from grain-noise predictions. The SNR, at a density of 0.7, was observed to increase from 50 to 85 as the number of exposures increased from one to four. For postexposure or preexposure holograms the maximum signal-to-noise and resolution peaked near an input moduation of 0.4.

19.
Appl Opt ; 13(1): 63-73, 1974 Jan 01.
Article in English | MEDLINE | ID: mdl-20125923

ABSTRACT

The variations in four-beam characteristics of a high repetition rate, giant pulse, ruby laser Lidar system were investigated as functions of five controllable laser parameters. The beam characteristics investigated were divergence, intensity distribution, directivity, and consistency of output energy. The variations in the laser beam characteristics were monitored as functions of ruby rod temperature, ruby rod quality, pumping repetition rate, cavity loss, and pumping energy. The resulting requirements on the pumping repetition rate in order to obtain minimums in laser beam divergence and deviation in the laser output energy were mutually exclusive. The results indicate that a laser oscillator-amplifier system with automatically controllable cavity mirrors would give more consistency in output energy and intensity distribution than lasers presently used in Lidar systems.

20.
Appl Opt ; 12(2): 417-8, 1973 Feb 01.
Article in English | MEDLINE | ID: mdl-20125304
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