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Biomedical subjects

D L Kerns

Publications and source records attributed to D L Kerns.

12 recordsLinked to original sources
PubMed2000

Impact of insecticides and surfactant on lettuce physiology and yield.

Insecticides are used extensively on lettuce, Lactuca sativa L., grown in southwestern Arizona because of heavy insect pressure that can potentially reduce lettuce productivity. Multiple sprays are made per season to manage these insects in lettuce. One of the major concerns related to extensive insecticide applications in lettuce is the potential subtle impact of insecticides that may reduce lettuce photosynthesis and yield. We conducted field and greenhouse experiments to examine the impact of multiple insecticides and surfactant spray applications on lettuce photosynthesis and yield. Lettuce was planted in the field in 1998, insecticides and surfactant were applied, and lettuce gas-exchange and dry weights were determined. Treatments were arranged in a split-plot consisting of insecticides as main plot and surfactant as subplot treatments in a randomized complete block design with four replications. Photosynthetic rates of lettuce were significantly reduced by endosulfan, methomyl, acephate, and surfactant at seedling stage 4 h and 2 d after the spray application was made. However, the reduction in lettuce photosynthesis by these insecticides and surfactant was only transient, and lettuce photosynthesis recovered 5 d after the spray application was made. Photosynthetic rates were not altered by zeta-cypermethrin, emamectin benzoate, and spinosad at the seedling stage. Insecticides or surfactant (Kinetic, a nonionic surfactant) did not significantly affect lettuce photosynthesis after rosette formation. In addition, lettuce dry weight was not significantly altered. These studies suggest that lettuce photosynthesis may be susceptible to some insecticides at the seedling stage. Consequently, we found that biorational insecticides, introduced to manage insect pests in lettuce, have no influence on lettuce physiology at the seedling stage, unlike the chlorinated hydrocarbons, organophosphates, or carbamates tested in this study. In a greenhouse study, we found that lettuce photosynthesis and yield were not altered by Bacillus thuringiensis application. Our results indicate that B. thuringiensis and the newer insecticides, particularly biorationals, can be used to manage lettuce insect pests without significantly altering lettuce gas-exchange and yield.

Animals↗
PubMed2000

Keys to a successful program.

Drug testing has proven to be an effective safety strategy. With proper planning, implementation, and technical expertise, a company can enjoy the benefits of a drug-free workplace. Should you wish to outsource this responsibility, there are some very good Program Administrators throughout the country, some national in scope and some regional. When recruiting an administrator, make sure it is capable of satisfying your needs. These may include a national collection site network with one fee for all your locations and with appointment scheduling, Medical Review Officers on staff with 24-hour availability, custom or standard policy and procedure manuals, training capabilities, the computing ability to customize your program, and the references to back up what the administrator claims. (Fact: If you don't test for drugs and all other employers in your area do, where do you think the drug users work?)

Humans↗
PubMed1992

Concave hymenal variations in suspected child sexual abuse victims.

The purpose of this study was to describe and analyze the characteristics of, and the clinical correlates to, concave hymenal variations in a large number of suspected child sexual abuse victims. Thirteen hundred eighty-three female child and adolescent suspected sexual abuse victims were comprehensively evaluated. Photocolposcopy was used for the anogenital examinations. Concave hymenal variations were found in 174 patients (12.6%). Sixty-one (35.1%) were anterior. Of these, 40 (65.6%) were curved and smooth, and 21 (34.4%) were angular and/or irregular. One hundred (57.5%) were posterior/lateral. Of these, 33 (33%) were curved and smooth, and 67 (67%) were angular and/or irregular. Thirteen patients (7.5%) had multiple hymenal concavities. Posterior/lateral location was associated with penile-vaginal contact (P = .004), penetration (P = .006), stranger perpetrator (P = .032), hymenal rim narrowing (P less than .001), and posterior fourchette abnormality (P = .049). Angular and/or irregular features were associated with penile contact (P = .005), vaginal contact (P = .035), penile-vaginal contact specifically (P less than .001), penetration (P = .046), abnormal general physical examination (P = .018), and hymenal rim narrowing (P less than .001). Logistic regression analysis demonstrated that age-specific prevalence trends for posterior/lateral (P less than .001) and angular and/or irregular (P = .011) concavities were consistent with acquired anatomic findings. An interobserver exercise with five "blinded" raters evaluating photographs of 49 patients showed significant agreement among observers in sorting posterior/lateral and angular concavities into the diagnostic categories "suggestive of trauma" and "trauma."(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

The role of physicians in reporting and evaluating child sexual abuse cases.

Physicians become involved in child sexual abuse when they must report suspected abuse or when they are asked to medically evaluate a child who is an alleged victim of abuse. This article reviews recent progress in the medical profession's attention to child sexual abuse and discusses current issues surrounding reporting and medical evaluation. The reporting requirement raises several concerns for pediatricians. Their legal responsibilities as reporters may conflict with their traditional relationship with the family as a unit and with the confidentiality of the doctor-patient relationship. Knowledge about pediatric anogential anatomy is in a relatively early stage of development, and few pediatricians receive training adequate to enable them to determine whether medical observations are consistent with sexual abuse. Even fewer pediatricians receive training in the unique considerations and needs present when taking the medical history of a possible abuse victim or when preserving evidence for possible later use in court. The medical evidentiary evaluation of suspected sexual abuse also raises a number of concerns. There is great variability in referral patterns, which determine whether a medical examination will be requested and whether a general practice physician or a specialist will be asked to conduct the exam. Although professional medical associations have laid out broad outlines of recommended procedures for medical exams when sexual abuse is suspected, more detailed protocols are needed for addressing the many cases where findings are ambiguous or subtle. Often physicians need training in forensics and assistance in coordinating services with multiple agencies and professions. Finally, attention must be given to ensuring adequate cost reimbursement for medical evaluations.

Child↗