It's OK to ask about past abuse.

Comments on the article by K. Becker-Blease and J. Freyd (see record 2006-03947-003), which addressed the ethics of asking and not asking research subjects about abuse. In their article, they systematically reviewed often-voiced concerns about and objections to asking questions about child maltreatment in survey research. They concluded that by failing to ask about a history of child maltreatment, an important predictor of later-life problems may be overlooked. The current authors discuss the Adverse Childhood Experiences (ACE) study, which provides strong evidence of the association between early traumatic experiences and some of the major public health problems facing our nation. Results from the ACE study have shown an association between traumatic childhood experiences and a broad range of health outcomes, including liver disease, ischemic heart disease, reproductive health, and mental illness, as well as a variety of health risks such as obesity, smoking, and alcoholism. The associations that these studies showed demonstrate that researchers studying health outcomes who do not ask study subjects about traumatic childhood experiences are overlooking an important risk factor for many of the major health issues of our day. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sequence and phylogenetic analyses of a new STLV-I from a naturally infected tantalus monkey from Central Africa

Simian T-cell leukemia virus (STLV-I) is an oncovirus highly related to human T-cell leukemia virus type I (HTLV-I). To further examine the extent of variability, dissemination patterns, phylogeny, and evolution of these viruses, we analyzed a new STLV-I variant from a naturally infected Cercopithecus aethiops var. tantalus from the Central African Republic. Sequence analyses of its LTR, gag, pol, env, and pX (OrfII) genes indicated that this isolate, STLV-I (Tan 90), is 6% divergent from the prototype HTLV-I (ATK) and is the most divergent African STLV-I characterized to date. Our phylogenetic data indicate that southeast Asian and African STLV-I and HTLV-I strains segregated from each other thousands of years ago and that Japanese HTLV-I strains represent a relatively recent introduction of African or New World isolates. The data also indicate that interspecies transmission occurred several times on different continents over prolonged periods of time.     

Effects of Terminal Sterilization on PEG‐Based Bioresorbable Polymers Used in Biomedical Applications

The effects of ethylene oxide (EO), vaporized hydrogen peroxide (VHP), gamma (γ) radiation, and electron‐beam (E‐beam) on the physiochemical and morphological properties of medical device polymers are investigated. Polymers with ether, carbonate, carboxylic acid, amide and ester functionalities are selected from a family of poly(ethylene glycol) (PEG) containing tyrosine‐derived polycarbonates (TyrPCs) to include slow, medium, fast, and ultra‐fast degrading polymers. Poly(lactic acid) (PLA) is used for comparison. Molecular weight (M_w) of all tested polymers decreases upon gamma and E‐beam, and this effect becomes more pronounced at higher PEG content. Gamma sterilization increases the glass transition temperature of polymers with high PEG content. EO esterifies the carboxylic acid groups in desaminotyrosol‐tyrosine (DT) and causes significant degradation. VHP causes hydroxylation of the phenyl ring, and hydrolytic degradation. This study signifies the importance of the chemical composition when selecting a sterilization method, and provides suggested conditions for each of the sterilization methods.

     

An Investigation of the Impacts of Agricultural Runoff on the Water Quality and Aquatic Organisms in a Lowveld Sand River System in Southeast Zimbabwe

In this research we examined the hypothesis that agricultural pollution is a key determinant of variability in nutrients concentrations and benthic fauna in a semi-arid tropical lowveld region of southeast Zimbabwe. Water quality was monitored in the river water column and river bottom sediments at a time when dissolved oxygen concentration was thought to be very low during the winter period in the rivers passing through low input agricultural sections and intensive commercial agricultural sections. The surveys used established chemical methods and biological methods. Benthic fauna assemblages were used to complement chemical cases of nutrient loading at localities chosen for sampling. Unpolluted control sites were not significantly different (t test, p < 0.05) from polluted sites in levels in mean values of dissolved oxygen, conductivity, total dissolved solids and mean density (no.m²) of benthic invertebrates in May. Significant differences (t test, p < 0.05) were not found in mean values of calcium, magnesium, potassium, total nitrogen, nitrate nitrogen, ammonia nitrogen and total phosphorous in river bottom sediments in May and August. These data certainly do not support the notion that the Runde River is severely polluted by the upstream agricultural activities and the hypothesis that agricultural runoff is a key determinant of water quality is rejected. As the data suggests the Runde River may be receiving moderate nutrient pollution. The positive effects of moderate eutrophication on fish catch and the trade-off in pollution implied here needs to be addressed by appropriate agricultural and environmental policies that relate to water pollution and land use.     

Recruiting the Host's Immune System to Target Helicobacter pylori's Surface Glycans

Due to the increased prevalence of bacterial strains that are resistant to existing antibiotics, there is an urgent need for new antibacterial strategies. Bacterial glycans are an attractive target for new treatments, as they are frequently linked to pathogenesis and contain distinctive structures that are absent in humans. We set out to develop a novel targeting strategy based on surface glycans present on the gastric pathogen Helicobacter pylori (Hp). In this study, metabolic labeling of bacterial glycans with an azide‐containing sugar allowed selective delivery of immune stimulants to azide‐covered Hp. We established that Hp's surface glycans are labeled by treatment with the metabolic substrate peracetylated N‐azidoacetylglucosamine (Ac₄GlcNAz). By contrast, mammalian cells treated with Ac₄GlcNAz exhibited no incorporation of the chemical label within extracellular glycans. We further demonstrated that the Staudinger ligation between azides and phosphines proceeds under acidic conditions with only a small loss of efficiency. We then targeted azide‐covered Hp with phosphines conjugated to the immune stimulant 2,4‐dinitrophenyl (DNP), a compound capable of directing a host immune response against these cells. Finally, we report that immune effector cells catalyze selective damage in vitro to DNP‐covered Hp in the presence of anti‐DNP antibodies. The technology reported herein represents a novel strategy to target Hp based on its glycans.     

Ferrous arrowheads and their oil quench hardening: Some early Indian evidence

A wide variety of ferrous arrowheads were in use in ancient India. Several typical chemical analyses of arrowheads found from archaeological excavation carried out at Kaushambi are reported in this paper. The average carbon content of these arrowheads varied from as low as 0.1 wt.% to approximately 0.9 wt.%. Literary evidence for oil quench hardening of ferrous arrowheads, as reported in famous Sanskrit epics—the Rāmāyana and the Mahābhārata—have been discussed in this paper. This type of quench hardening was intentionally adopted as it helped in preventing distortion and formation of quench cracks in arrowheads. The oil quench-hardened arrowheads were rubbed on stones to sharpen them, which also brought about tempering of martensite due to frictional heat.     

Moisture conservation and nitrogen recycling through legume mulching in rainfed maize (<Emphasis Type="Italic">Zea mays</Emphasis>)–wheat (<Emphasis Type="Italic">Triticum aestivum</Emphasis>) cropping system

Mulching with vegetative materials is a highly beneficial and widely-investigated agro-technique in rainfed areas but the adoption of this practice has been constrained due to non-availability of mulch biomass locally. Live mulching with fast-growing annual green manure legumes like sunnhemp (Crotalaria juncea) or prunings of Leucaena leucocephala grown as hedge rows can be done for moisture conservation as well as nutrient cycling in the maize–wheat cropping system, which is predominantly followed in the high rainfall sub-mountainous region of north-western India. A field experiment was conducted at Selakui, Dehradun during 2000–2004 to study the effect of legume mulching, viz. in situ grown sunnhemp and Leucaena prunings, along with varying N levels, viz. 0, 30, 60 and 90 kg N ha⁻¹ (to maize), and 0, 40 and 80 kg N ha⁻¹ (to wheat) on productivity, soil moisture conservation and soil physico-chemical properties. Intercropped sunnhemp added 0.75–1.45 t dry matter and 21.6–41.3 kg N ha⁻¹ at 30–35 days, while Leucaena twigs added 1.89–4.15 t dry matter and 75.2–161.3 kg N ha⁻¹ at 60–65 days of maize growth. Live mulching with sunnhemp or Leucaena biomass improved soil moisture content at maize harvest (+1.15–1.57%) and crop productivity by 6.8–8.8% over no mulching. Combined use of both the mulching materials was more effective in improving the soil moisture content (+2.08–2.29%) and grain yield (15.1%) over their single application. Response of maize to N fertilizer application was significant up to 90 kg N ha⁻¹, and it was relatively more pronounced under the mulching treatments. Residual effect of mulching on wheat showed an increase in yield of 10.2% with sunnhemp or Leucaena, and 27.9% with sunnhemp + Leucaena. There was an improvement in organic C and total N status of soil, and a decrease in bulk density associated with an increase in infiltration rate due to mulching at the end of 4 cropping cycles. It was concluded that legume mulching is a highly beneficial practice for enhanced moisture and nutrient conservation, leading to increased productivity and soil health of maize–wheat cropping system under Doon valley conditions of north-western India.     

The extraction of lead from its ores by the iron-reduction process: A historical perspective

The iron-reduction process for extracting lead from its ores, as practiced in different parts of the world, is reviewed and discussed in this paper based on literary and documentary evidence. It has been shown that the early 14th century Indian reference of Thakkura Pherū appears to be the first evidence on this subject. This process was most vigorously adopted for the production of lead in Germany during the 18th and 19th centuries. Developments in the original iron-reduction process were also carried out in Germany, wherein the reductant iron was produced in-situ by the carbothermic reduction of iron-bearing material in the lead smelter itself. This process eventually replaced the original iron-reduction process in Germany in the later part of the 19th century.     

Good as new

This work describes the process involved in evaluating whether or not to reuse the generator's original compound excitation system and, if replaced, the type of excitation system that should be installed: compound or potential bus-fed type. It was determined that installing a used steam turbine generator at the plant would be a viable way to reduce manufacturing costs. This work discusses the issues encountered during the evaluation process, the expectations desired, the decisions made, and the outcome achieved as a result of the final decision to replace the existing compound excitation system with a potential bus-fed excitation system.