Modeling the proportion of cut slopes rock on forest roads using artificial neural network and ordinal linear regression.

Rock proportion of subsoil directly influences the cost of embankment in forest road construction. Therefore, developing a reliable framework for rock ratio estimation prior to the road planning could lead to more light excavation and less cost operations. Prediction of rock proportion was subjected to statistical analyses using the application of Artificial Neural Network (ANN) in MATLAB and five link functions of ordinal logistic regression (OLR) according to the rock type and terrain slope properties. In addition to bed rock and slope maps, more than 100 sample data of rock proportion were collected, observed by geologists, from any available bed rock of every slope class. Four predictive models were developed for rock proportion, employing independent variables and applying both the selected probit link function of OLR and Layer Recurrent and Feed forward back propagation networks of Neural Networks. In ANN, different numbers of neurons are considered for the hidden layer(s). Goodness of the fit measures distinguished that ANN models produced better results than OLR with R (2) = 0.72 and Root Mean Square Error = 0.42. Furthermore, in order to show the applicability of the proposed approach, and to illustrate the variability of rock proportion resulted from the model application, the optimum models were applied to a mountainous forest in where forest road network had been constructed in the past.

Fungal sinusitis in patients with AIDS: report of 4 cases and review of the literature.

We report here 3 cases of aspergillus sinusitis in patients with AIDS and the 1st fully described case, to our knowledge, of sinusitis associated with Pseudallescheria boydii in a patient with AIDS. We review the microbiology and pathology of fungal sinusitis in patients with AIDS and the morphologic and clinical features and treatment of P. boydii infection and aspergillus sinusitis. Fungal sinusitis in patients with HIV or AIDS generally occurs later in the course of primary disease with low CD4+ lymphocyte counts (< 50/mm3), unlike bacterial sinusitis which may occur at any time. Differentiation between invasive and noninvasive forms is likely not important, in contrast to fungal sinusitis in noncompromised patients. The number of cases is likely to increase as the number of patients with AIDS increases, patients survive longer, and other opportunistic infections are prevented or treated. Causative agents are likely to be resistant to fluconazole, which is in widespread use. Aspergillus sinusitis in patients with HIV or AIDS occurs in both those with and without traditional risk factors. Fungal sinusitis may present vexing management problems and be relentlessly progressive in the face of therapy. Ideal therapy has yet to be defined but an early combined surgical and medical approach in these compromised patients is preferred.

Dermatosis papulosa nigra in a young child.

Dermatosis papulosa nigra was diagnosed in a 3-year-old black boy. This follicular nevoid condition, which is common in adult blacks, is seldom diagnosed in prepubescent children. The diagnosis was confirmed by the biopsy specimen that showed features of epidermal acanthosis and papillomatosis, similar to seborrheic keratosis.

Current trends in laser blepharoplasty. Results of a survey.

BACKGROUND: The use of lasers in cosmetic surgery has been expanded fairly recently to include blepharoplasties. Controversy exists as to the efficacy of this procedure. This survey is designed to gain an understanding of the efficacy of blepharoplasty performed by laser versus conventional scalpel techniques. METHODS: A group of surgeons who perform the procedure were questioned. Over 4,000 cases of upper and lower lid laser blepharoplasty were reported by the responding physicians. RESULTS: The results of this survey indicate that carbon dioxide is by far the most common laser used in laser blepharoplasty (96%). A laser is used as a sole cutting tool by 70% of the responders and as a sole hemostasis tool by 88% of surgeons. Overall, both the intraoperative time and postoperative recovery period were reported as significantly reduced when blepharoplasty is performed by laser as compared with scalpel. In general, the incidences of edema, ecchymosis, and postoperative pain were reported as less severe with laser. No serious complications related to the laser were documented by the survey responders. CONCLUSIONS: This study confirms that laser blepharoplasty techniques can be safe and effective in skilled hands and may even have some potential advantages over conventional blepharoplasty.

Cutaneous acanthamoebiasis in AIDS.

Acanthamoeba is a recognized pathogen in the immunocompromised patient, commonly presenting as chronic or subacute encephalitis. However, cutaneous disease in the absence of CNS involvement is increasingly recognized, especially in the setting of chronic, nonhealing skin lesions in the patient with AIDS. We describe a patient with AIDS and cutaneous acanthamoebiasis and review our experience with treatment and diagnosis.

Clinical improvement of photoaged skin with 50% glycolic acid. A double-blind vehicle-controlled study.

BACKGROUND: Although there is increasing interest in the use of glycolic acid in the treatment of photoaged skin, to our knowledge, no controlled study has been done to assess the efficacy or the mode of this agent. OBJECTIVE: The purpose of this study was to determine whether 50% glycolic acid can improve photoaged skin and to study the histological basis for this improvement. METHODS: Forty-one volunteers were recruited into this double-blind vehicle-controlled study. Glycolic acid (50%) or vehicle was applied topically for 5 minutes to one side of the face, forearms, and hands, once weekly for 4 weeks. Punch biopsies were taken at pretherapy and at 5 weeks for histologic study. RESULTS: Significant improvement noted included decrease in rough texture and fine wrinkling, fewer solar keratoses, and a slight lightening of solar lentigines. Histology showed thinning of the stratum corneum, granular layer enhancement, and epidermal thickening. Some specimens showed an increase in collagen thickness in the dermis. CONCLUSION: The results of this study demonstrate that the application of 50% glycolic acid peels improves mild photoaging of the skin.