Mutualism disruption by an invasive ant reduces carbon fixation for a foundational East African ant-plant.

Invasive ants shape assemblages and interactions of native species, but their effect on fundamental ecological processes is poorly understood. In East Africa, Pheidole megacephala ants have invaded monodominant stands of the ant-tree Acacia drepanolobium, extirpating native ant defenders and rendering trees vulnerable to canopy damage by vertebrate herbivores. We used experiments and observations to quantify direct and interactive effects of invasive ants and large herbivores on A.

Frenemy at the gate: Invasion by Pheidole megacephala facilitates a competitively subordinate plant ant in Kenya.

Biological invasions can lead to the reassembly of communities and understanding and predicting the impacts of exotic species on community structure and functioning are a key challenge in ecology. We investigated the impact of a predatory species of invasive ant, Pheidole megacephala, on the structure and function of a foundational mutualism between Acacia drepanolobium and its associated acacia-ant community in an East African savanna. Invasion by P.

Are there differences in zonal distribution and tumor volume of prostate cancer in patients with a positive family history?

Purpose: To determine if there are any differences in the zonal distribution and tumor volumes of familial and sporadic prostate cancers (PC) in men undergoing radical prostatectomy.

Material And Methods: 839 patients underwent a radical prostatectomy in the absence of prior neoadjuvant therapy between 1987 and 1996. Telephone interviews were conducted to obtain an updated family history.

Way out of Africa: Early Pleistocene paleoenvironments inhabited by Homo erectus in Sangiran, Java.

A sequence of paleosols in the Solo Basin, Central Java, Indonesia, documents the local and regional environments present when Homo erectus spread through Southeast Asia during the early Pleistocene. The earliest human immigrants encountered a low-relief lake-margin landscape dominated by moist grasslands with open woodlands in the driest landscape positions. By 1.

Metastatic penile cancer in a young Caucasian male: impact of delayed diagnosis.

Penile cancer is an uncommon malignancy in the developed world, with only 1200 estimated cases per year in the United States. This is usually a cancer of older men and often the diagnosis is delayed because of lack of suspicion on the part of the patient or primary care provider. We report a case of penile cancer in a young Caucasian male in whom a delay in diagnosis had a deleterious impact on outcome.

Meckel's diverticulitis secondary to carcinoid tumor: an unusual presentation of the acute abdomen in an adult.

This case reports the concomitant findings of carcinoid tumor within a Meckel's diverticulum presenting as an acute abdomen in an adult male. Most Meckel's diverticula remain asymptomatic throughout life, and symptomatic diverticula are virtually nonexistent in older adults. Meckel's diverticulitis is clinically indistinguishable from acute appendicitis, and abnormal or symptomatic diverticula are generally resected.

Surgical management of renal cell carcinoma associated with complex inferior vena caval thrombi.

The operative morbidity and mortality of radical nephrectomy are considerably higher when the vena cava is involved by the tumor. The prognostic significance of vena caval extension in this setting remains controversial. We reviewed our experience of vena caval thrombectomy specifically addressing prognostic factors.

Migration of a Late Cretaceous fish.

Late Cretaceous sediments from the Western Interior of North America yield exceptionally well preserved fossils that serve as proxies for the rapidly changing climate preceding the Cretaceous/Tertiary boundary (about 67-65 Myr ago). Here we reconstruct the ontogenetic history of a Maastrichtian-age fish, Vorhisia vulpes, by using the carbon, oxygen and strontium isotope ratios of four aragonite otoliths collected from the Fox Hills Formation of South Dakota. Individuals of V.

Nanosecond generation of tyrosyl radicals via laser-initiated decaging of oxalate-modified amino acids.

We describe a general method for the unimolecular photochemical generation of tyrosyl radicals from a diaryl oxalate ester platform on the nanosecond time scale. Symmetric and asymmetric tyrosine oxalate esters have been prepared in gram quantities. Direct photocleavage of the oxalate linkage by laser flash photolysis affords tyrosyl radicals within 50 ns.

Assessment of personal protective equipment use among Midwestern farmers.

Background: Personal protective equipment (PPE) is readily available and widely recommended, yet usage among agricultural workers is largely unknown.

Methods: A mail survey of 2,483 farmers in six Midwestern states with telephone follow-up addressed PPE usage related to sun exposure, noise abatement, chain saw usage, welding and metal work, handling of large animals in and out of confinement facilities, feed handling, manure storage facilities, and mixing and applying chemicals. Summary statistics of survey responses were compiled.

Structural, spectroscopic, and reactivity comparison of xanthene- and dibenzofuran-bridged cofacial bisporphyrins.

A comparison of the structure, spectroscopy, and oxygen atom-transfer reactivity of cofacial bisporphyrins anchored by xanthene (DPX) and dibenzofuran (DPD) pillars is presented. The synthesis and characterization of dicopper(II) and dinickel(II) complexes of DPD completes a homologous series of homobimetallic zinc(II), copper(II), and nickel(II) complexes for both cofacial platforms. X-ray crystallographic analysis of the parent free-base porphyrins H(4)DPX (1) and H(4)DPD (5) confirms the face-to-face arrangement of the two porphyrin macrocycles with a large available range of vertical pocket sizes: 1 (C(80)H(92)Cl(2)N(8)O), triclinic, space group P1 macro, a = 13.