The Early Evolution of Biting–Chewing Performance in Hexapoda

Insects show a plethora of different mandible shapes. It was advocated that these mandible shapes are mainly a function of different feeding habits. This hypothesis was tested on a larger sampling of non-holometabolan biting–chewing insects with additional tests to understand the interplay of mandible function, feeding guild, and phylogeny. The results show that at the studied systematic level, variation in mandible biting–chewing effectivity is regulated to a large extent by phylogenetic history and the configuration of the mandible joints rather than the food preference of a given taxon. Additionally, lineages with multiple mandibular joints such as primary wingless hexapods show a wider functional space occupation of mandibular effectivity than dicondylic insects (= silverfish + winged insects) at significantly different evolutionary rates. The evolution and occupation of a comparably narrow functional performance space of dicondylic insects is surprising given the low effectivity values of this food uptake solution. Possible reasons for this relative evolutionary “stasis” are discussed

Functional correlates of skull shape in Chiroptera: feeding and echolocation adaptations.

Morphological, functional and behavioural adaptations of bats are among the most diverse within mammals. A strong association between bat skull morphology and feeding behaviour has been suggested previously. However, morphological variation related to other drivers of adaptation, in particular echolocation, remains understudied. We assessed variation in skull morphology with respect to ecology (diet and emission type) and function (bite force, masticatory muscles and echolocation characteristics) using geometric morphometrics and comparative methods. Our study suggests that variation in skull shape of 10 bat families is the result of adaptations to broad dietary categories and sound emission types (oral or nasal). Skull shape correlates with echolocation parameters only in a subsample of insectivorous species, possibly because they (almost) entirely rely on this sensory system for locating and capturing prey. Insectivores emitting low frequencies are characterised by a ventrally tilted rostrum, a trait not associated with feeding parameters. This result questions the validity of a trade-off between feeding and echolocation function. Our study advances understanding of the relationship between skull morphology and specific features of echolocation and suggests that evolutionary constraints due to echolocation may differ between different groups within the Chiroptera

Small mammals from Kuala Atok-Taman Negara Pahang, Malaysia

A faunal survey aimed to document small mammals was conducted at Nature Study Centre of Kuala Atok, Taman Negara Pahang from 16th to 23rd May 2008. This survey was part of the Biodiversity Inventory Programme that was organised by the Department of Wildlife and National Parks (DWNP). On average, ten mist nets, two four-bank harp traps, 100 cage traps and 40 Sherman traps were set for six trapping nights. A total of 79 individuals from three orders, seven families and 23 species were caught in this study. Of the 23 species, three were frugivorous bats, 15 were insectivorous bats, four were rodents and one was treeshrew. Our sampling site was bounded by Pahang River and mainly covered with lowland secondary forest. This is evidence by the highest abundance of Long-tailed Giant Rat (Leopoldamys sabanus) for non-volant small mammals, and Fawn Roundleaf Bat (Hipposideros cervinus) for volant small mammals that are adapted to disturbed habitat. The increasing species cumulative curve for Chiropteran indicates that there may be more species yet to be recorded from this study site compared to rodents and treeshrews. Preliminary analysis on the species similarity between our study site to other survey reports in Peninsular Malaysia, positioned Kuala Atok with Krau Wildlife Reserve and Bukit Fraser Forest Reserve that are located adjacent to our study site. This similarity further indicate the importance of future survey in Kuala Atok especially for Chiropterans to properly document the species diversity in this site that may be as rich as other well studied area e.g. Krau Wildlife Reserve

The effect of temperature treatment on structural and optical properties of cr3+doped alumina nanocrystals

Cr3+doped alumina nanocrystals have been successfully prepared using combustion method. The chemicals used in this preparation are aluminium nitrate, chromium nitrate, urea and glucose. All these chemicals were thoroughly mixed then heated in a furnace. The mixture was heated at 600 °C for 1 hour then heated at 700, 800 and 900 °C for 30 minutes. At the final stage the mixture was heated at the temperature of 1000 °C for 30, 60, and 120 minutes. At every different temperature and heating time, some of the sample was taken for analysis. The samples were analysed in terms of their structure and optical properties by using X-ray diffraction (XRD) and spectrofluorometer, respectively. From the analysis, it is found that the structure and optical properties were strongly affected with the temperature and heating time. The sample heated at 1000 °C for 30 minutes contains gamma and alpha phases structures. The structure fully transformed to alpha phase after 1 hour of heating at 1000 °C. From the X-ray diffractogram, crystallite size was estimated using Scherrer equation, which shows increasing trend from 21 nm to 33 nm as the heating time prolonged from 30 minutes to 120 minutes at 1000 °C. The fluorescence spectra at 694 nm observed for the samples annealed at 1000 °C. The intensity of fluorescence increases with longer heating time. Based on the result, it shows that the temperature and heating time significantly influence the structure and fluorescence intensity

Neuroprotective effects of a variety of pomegranate juice extracts against MPTP-induced cytotoxicity and oxidative stress in human primary neurons

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is an environmental toxin which selectively induces oxidative damage and mitochondrial and proteasomal dysfunctions to dopaminergic neurons in the substantia nigra leading to Parkinsonian syndrome in animal models and humans. MPTP is one of the most widely used in vitro models to investigate the pathophysiology of Parkinson's disease (PD) and, screen for novel therapeutic compounds that can slow down or ameliorate this progressive degenerative disease. We investigated the therapeutic effect of pomegranate juice extracts (PJE), Helow, Malasi, Qusum, and Hamadh against MPTP-induced neurotoxicity in primary human neurons by examining extracellular LDH activity, intracellular NAD⁺ and ATP levels, and endogenous antioxidant levels including lipid peroxidation products, catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, and reduced glutathione (GSH) levels. MPTP induced a reduction in SOD and GPx activities and intracellular NAD⁺, ATP, and GSH levels parallel to an increase in extracellular LDH and CAT activities, although lipid peroxidation was not altered. We report that helow and malasi can ameliorate MPTP-induced neurotoxicity by attenuating the observed changes in redox function to a greater extent than qusum and hamedh. Selected PJE varieties may exhibit properties which may be of therapeutic value to slow down age-related degeneration and neurodegeneration in particular.12 page(s

Septo-optic Dysplasia

Purpose Septo-optic dysplasia is a congenital disorder consisting of optic nerve hypoplasia and absent septum pellucidum. While associated anomalies have been described, olfactory sulcus and bulb-tract hypoplasia have been scantily reported and was the focus of this study. Methods The picture archival and communications system and radiology information system (PACS-RIS) was searched over 15 years for patients with suspected septo-optic dysplasia (n = 41) and cerebral magnetic resonance imaging (MRI). Included patients had coronal (<= 3 mm), axial (<= 4 mm), and sagittal (<= 4 mm) imaging reviewed by two staff neuroradiologists by consensus. Both olfactory sulcus and bulb-tract hypoplasia were ascribed a grade of 0 (normal) to 3 (complete hypoplasia). Other associated congenital anomalies were recorded, if present. Incidence of anomalies were compared to age-matched and gender-matched control patients. Results Out of 41 septo-optic dysplasia patients 33 were included (mean age = 120.7 months), with 8 excluded due to isolated septum pellucidum absence (n = 5), isolated bilateral optic hypoplasia (n = 2), or inadequate imaging (n = 1). An olfactory sulcus was hypoplastic on one or both sides in 14/33 (42.4%). Olfactory bulb hypoplasia was noted in one or both tracts in 15/33 (45.4%). A significant correlation was found between degree of olfactory sulcal and bulb-tract hypoplasia (rho = 0.528, p = 0.0009). Other anomalies were: anterior falx dysplasia (n = 16, 48.5%), incomplete hippocampal inversion (n = 14, 42.4%), polymicrogyria (n = 11, 33.3%), callosal complete or partial agenesis (n = 10, 30.3%), schizencephaly (n = 8, 24.2%), ectopic posterior pituitary (n = 6, 18.2%), and nodular heterotopia (n = 4, 12.1%). Of the age-matched control patients 10/33 (30.3%) had at least mild anterior falx hypoplasia, and 1 control patient was noted to have unilateral incomplete hippocampal inversion (IHI); none of the age-matched control patients had olfactory sulcus or bulb-tract hypoplasia. Conclusion Olfactory sulcus and bulb-tract hypoplasia are fairly common in septo-optic dysplasia and can be discordant between sides. Of the other associated anomalies, anterior falx dysplasia seems to be the most common