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Using the Chinese writing system, which is unique with respect to the composition of each character in terms of its graphic shape, as an example, this chapter addresses the neurobiological underpinnings of reading and writing and how these brain circuits are used in different languages.

Electret ion chambers (EICs) are inexpensive, lightweight, robust, commercially available, passive, charge-integrating devices for measuring different radiations. At Florida International University's Hemispheric Center for Environmental Technology (FIU-HCET), EIC performance was evaluated with the goal of providing the U.S. Department of Energy (DOE) with a low-cost, low-risk means of alpha contamination monitoring using an existing commercial technology. During this evaluation, sensitivity of electrets in 960-mL hemispherical ion chamber (radius: 7.6 cm) was observed to increase with alpha particle energy because alpha particles expended their entire energy in the chamber volume. This observation prompted us to explore another EIC application: estimation of alpha particle energy. Correlation between electret mid-point voltage, alpha particle energy, and response was developed for the 960-mL EIC and was used to determine energy of an unknown source. The response (change in voltage per disintegration) is the ratio of the change of voltage per unit time and alpha particle activity. Sincean EIC measures only the change in voltage per minute, to determine the alpha particle energy, the source activity should be accurately determined by another method. [ABSTRACT FROM AUTHOR]

Spotted fever (SF) is an important treatable cause of acute febrile illness (AFI) with rash and has reemerged in India. A prospective AFI with rash study was undertaken at a South Indian hospital to correlate specific clinical findings with laboratory confirmation of spotted fever. During the study period (December 2017 to May 2019), 175 patients with fever and rash were suspected to have spotted fever. Molecular assays for scrub typhus and spotted fever (47 kDa and ompA qPCR) and serology (IgM ELISA) was performed on the 96 individuals recruited. Laboratory confirmed SF cases (ompA qPCR positive) were 21, whereas laboratory supported SF cases (ompA negative but sero-positive by SF IgM ELISA) were 27. Among the 48 spotted fever (SF) cases, 70% of had maculopapular rash, 12.5% had macular rash, purpuric/petechial rash (severe rash) was seen in 8 patients (16.7%). Presence of rash on the palms and soles was associated with a relative risk (RR) of 4.36 (95% CI: 2.67-7.10; p < 0.001). Our study suggests that ompA qPCR though useful for confirming the diagnosis of spotted fever is not always positive. A positive SF IgM ELISA in febrile individuals with palmo-plantar rash supports the diagnosis of spotted fever especially when other causes of febrile rash have been excluded. Multi-centric prospective studies employing the serological reference standard, IFA (immunofluorescence assay) in addition to the assays used in this study are needed to validate these findings.

Exposure to Bisphenol A (BPA) has been reported to dysregulate endocrine pathways in a wide array of vertebrate species. The effects of BPA on invertebrate species are less well understood. We tested the effects of BPA on growth and development in Drosophila as these processes are governed by well-studied endocrine pathways. In this study, we tested the effects of three concentrations of BPA (0.1mg/L, 1mg/L or 10mg/L) and found a statistically significant increase in larval growth for the low dose treatment group (0.1mg/L), but not statistically significant for the high dose treatment group (10mg/L). BPA exposure resulted in an increased body size in treated animals at 48, 72 and 96h after egg laying (AEL). This finding reflects a non-monotonic dose-response that has been observed for an increasing number of endocrine disrupting compounds. The increase in growth rate found for all treatment groups was associated with a statistically significant increase in food intake observed at 72h AEL. Furthermore, we observed that the increased growth rate was coupled with an earlier onset of pupariation consistent with previously reported phenotypes resulting from increased activity of insulin/insulin growth factor signaling (IIS) in Drosophila. Since the timing of the onset of pupariation in Drosophila is controlled through the complex interaction of the IIS and the ecdysone signaling pathways, our findings suggest that BPA exerts its effects through disruption of endocrine signaling in Drosophila., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The Tasmanian bettong (Bettongia gaimardi) is a small rat-kangaroo (marsupial) found only in Tasmania, Australia. The duration of pouch life is 15 weeks. Adults and older young display non-shivering thermogenesis and this paper examines the role of thyroxine in the development of endothermy in pouch young. Free thyroxine (T4) concentrations varied throughout pouch life. The mean (+/-SE) concentration was 6.2+/-1.9 pmol L(-1) in week 7, increased and peaked at 19.2+/-4.3 pmol L(-1) in week 12, and declined to 5.6+/-0.4 pmol L(-1) by week 20. This was similar to adult levels (3.2+/-3.8 pmol L(-1)). These concentrations showed significant differences. From pouch week 12 onwards, T4 injection raised oxygen consumption. Maximum levels of VO2 after T4 injection occurred at weeks 14-15. Although adult levels were lower, the increase in adult oxygen consumption after T4 injection was about 50%. Peak free T4 levels and metabolic responses to nor-adrenalin occur at week 12 and we hypothesize that thyroid hormone may facilitate the development of adrenergic-receptors in this species. The data presented in the paper further attest to the likely important role of the thyroid gland in the development of endothermy in marsupial pouch young.

The Tasmanian bettong (Bettongia gaimardi, a marsupial) is a rat-kangaroo that increases nonshivering thermogenesis (NST) in response to norepinephrine (NE). This study attempted to assess whether brown adipose tissue (BAT), a specialized thermogenic effector, is involved in NST in the bettong. Regulatory NST, indicated by resting oxygen consumption (Vo2) of the whole body, was measured under conscious conditions at 20 degrees C with various stimuli: cold (4 degrees -5 degrees C) or warm (25 degrees C) acclimation, NE injection, and the beta3-adrenoceptor agonist (BRL) 37344. In line with the functional studies in vivo, the presence of BAT was evaluated by examining the expression of the uncoupling protein 1 (UCP1) with both rat cDNA and oligonucleotide probes. Both NE and BRL 37344 significantly stimulated NST in the bettong. After cold acclimation of the animals (at 4 degrees -5 degrees C for 2 wk), the resting Vo2 was increased by 15% and the thermogenic effect of NE was enhanced; warm-acclimated animals showed a slightly depressed response. However, no expression of UCP1 was detected in bettongs either before or after cold exposure (2 wk). These data suggest that the observed NST in the marsupial bettong is not attributable to BAT.

Microvascular dysfunction due to endothelial damage is often associated with the ionizing radiation used during cancer therapy. This radiation-induced capillary injury is a major factor in the inhibition of new vessel growth (angiogenesis) and in disease states such as radiation-induced pneumonitis and nephropathy. Many studies have examined the effects of radiation on endothelial cell function; however, little is known regarding the role the basement membrane plays in radiation-induced endothelial cell damage and angiogenesis. Therefore, we examined the effects of gamma radiation on aortic explants, and in vitro on three endothelial cell types (of artery, vein and capillary origin) irradiated with or without the basement membrane glycoprotein laminin-1. As expected, irradiation inhibited angiogenic sprouting of the aortic explants, endothelial cell proliferation, attachment, migration and differentiation in vitro in a dose-dependent manner. However, the effect of radiation on several of these processes in angiogenesis was reduced when the cells were irradiated on laminin-1. To further evaluate the effects of radiation on endothelial cells, we examined the expression of the vascular endothelial cell growth factor (VEGF) kinase domain region receptor in endothelial cells irradiated in the presence and absence of laminin-1. In endothelial cells irradiated on laminin-1, KDR expression increased 2.5-fold over control levels. Therefore, although radiation has a dose-dependent inhibitory effect on processes associated with angiogenesis in vitro, the presence of the basement membrane glycoprotein laminin-1 during irradiation decreases these effects.

Bettongs give birth on the night that their large pouch young finally vacates the pouch. We have hypothesized that hormones associated with this birth are also involved in pouch vacation. Injections of prostaglandin F2 alpha (PGF2 alpha) caused contractions of the pouch. In a separate experiment PGF2 alpha caused pouch vacation; oxytocin had a similar effect but with a longer latency. In addition both hormones induced birth behavior in adult and immature females as well as in males. When a prostaglandin synthesis inhibitor (Finadyne) was given first, oxytocin failed to produce birth behavior or pouch vacation. This finding leads us to suggest that oxytocin exerts its behavioral effects via prostaglandin synthesis. These experiments are the first to demonstrate an effect by oxytocin on reproductive behavior in a marsupial.

Many macropodids exhibit lactational quiescence during which an embryo produced at post-partum mating is retained as a blastocyst in utero while a pouch young is sucking. The sucking stimulus maintains secretion of prolactin which may in some species inhibit the activity of the corpus luteum and, hence, the development of the embryo. When the sucking frequency decreases, the blastocyst resumes development. In the present study, the dopamine agonist bromocriptine, which in many mammals results in decreased secretion of prolactin from the pituitary gland, was administered to the Tasmanian bettong (Bettongia gaimardi) at two different doses (12.5 mg kg(-1) and 5 mg kg(-1)). Although lactation was affected by both doses, as evidenced by slower growth of the pouch young or their loss, in only two cases did the quiescent blastocyst activate at the time of injection. This occurred with the highest dose of bromocriptine and was reflected by earlier changes in plasma progesterone concentrations. It is concluded that the Tasmanian bettong is unusual in its lack of sensitivity to bromocriptine.

Basal body temperature, quantitative changes in vaginal smears and plasma concentrations of progesterone were measured during a number of oestrous cycles in Tasmanian bettongs (Bettongia gaimardi). These methods of monitoring the reproductive cycle were compared in an attempt to find a technique that allowed non-stressful assessment of the reproductive condition of the bettongs. Telemetric measurement of basal body temperature showed that there was a diurnal variation of 1.3 degrees C, typical of a nocturnal animal. During the oestrous cycle, there was a small, but not significant, peak in basal body temperature at oestrus (day 0) followed by a significant trough on day 2. There was a significant increase on day 3 and the temperature remained raised until day 10, during which time plasma progesterone concentrations are also high; the temperature then fell 2 days before oestrus. This fall corresponds to a decrease in concentration of plasma progesterone and in the numbers of leucocytes in vaginal smears. Telemetric measurement of body temperature may be useful as a non-stressful method of monitoring the oestrous cycle in bettongs.