577 research outputs found

    Oil palm cultivation critically affects sociality in a threatened Malaysian primate

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    Human-induced habitat alterations globally threaten animal populations, often evoking complex behavioural responses in wildlife. This may be particularly dramatic when negatively affecting social behaviour, which fundamentally determines individual fitness and offspring survival in group-living animals. Here, we provide first evidence for significant behavioural modifications in sociality of southern pig-tailed macaques visiting Malaysian oil palm plantations in search of food despite elevated predation risk. Specifically, we found critical reductions of key positive social interactions but higher rates of aggression in the plantation interior compared to the plantation edge (i.e. plantation areas bordering the forest) and the forest. At the plantation edge, affiliation even increased compared to the forest, while central positions in the macaques' social network structure shifted from high-ranking adult females and immatures to low-ranking individuals. Further, plantations also affected mother-infant relationships, with macaque mothers being more protective in the open plantation environment. We suggest that although primates can temporarily persist in human-altered habitats, their ability to permanently adapt requires the presence of close-by forest and comes with a trade-off in sociality, potentially hampering individual fitness and infant survival. Studies like ours remain critical for understanding species’ adaptability to anthropogenic landscapes, which may ultimately contribute to facilitating their coexistence with humans and preserving biodiversity

    Analysis of Solar-Heated Thermal Wadis to Support Extended-Duration Lunar Exploration

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    The realization of the renewed exploration of the moon presents many technical challenges; among them is the survival of lunar-surface assets during periods of darkness when the lunar environment is very cold. Thermal wadis are engineered sources of stored solar energy using modified lunar regolith as a thermal storage mass that can supply energy to protect lightweight robotic rovers or other assets during the lunar night. This paper describes an analysis of the performance of thermal wadis based on the known solar illumination of the moon and estimates of producible thermal properties of modified lunar regolith. Analysis has been performed for the lunar equatorial region and for a potential outpost location near the lunar south pole. The calculations indicate that thermal wadis can provide the desired thermal energy and temperature control for the survival of rovers or other equipment during periods of darkness

    Analysis of Solar-Heated Thermal Wadis to Support Extended-Duration Lunar Exploration

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    The realization of the renewed exploration of the Moon presents many technical challenges; among them is the survival of lunar surface assets during periods of darkness when the lunar environment is very cold. Thermal wadis are engineered sources of stored solar energy using modified lunar regolith as a thermal storage mass that can enable the operation of lightweight robotic rovers or other assets in cold, dark environments without incurring potential mass, cost, and risk penalties associated with various onboard sources of thermal energy. Thermal wadi-assisted lunar rovers can conduct a variety of long-duration missions including exploration site surveys; teleoperated, crew-directed, or autonomous scientific expeditions; and logistics support for crewed exploration. This paper describes a thermal analysis of thermal wadi performance based on the known solar illumination of the moon and estimates of producible thermal properties of modified lunar regolith. Analysis was performed for the lunar equatorial region and for a potential Outpost location near the lunar south pole. The results are presented in some detail in the paper and indicate that thermal wadis can provide the desired thermal energy reserve, with significant margin, for the survival of rovers or other equipment during periods of darkness

    Dynamical cluster-decay model for hot and rotating light-mass nuclear systems, applied to low-energy 32^{32}S + 24^{24}Mg →56\to ^{56}Ni reaction

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    The dynamical cluster-decay model (DCM) is developed further for the decay of hot and rotating compound nuclei (CN) formed in light heavy-ion reactions. The model is worked out in terms of only one parameter, namely the neck-length parameter, which is related to the total kinetic energy TKE(T) or effective Q-value Qeff(T)Q_{eff}(T) at temperature T of the hot CN, defined in terms of the both the light-particles (LP), with A≀A \leq 4, Z ≀\leq 2, as well as the complex intermediate mass fragments (IMF), with 424 2, is considered as the dynamical collective mass motion of preformed clusters through the barrier. Within the same dynamical model treatment, the LPs are shown to have different characteristics as compared to the IMFs. The systematic variation of the LP emission cross section σLP\sigma_{LP}, and IMF emission cross section σIMF\sigma_{IMF}, calculated on the present DCM match exactly the statistical fission model predictions. It is for the first time that a non-statistical dynamical description is developed for the emission of light-particles from the hot and rotating CN. The model is applied to the decay of 56^{56}Ni formed in the 32^{32}S + 24^{24}Mg reaction at two incident energies Ec.m._{c.m.} = 51.6 and 60.5 MeV. Both the IMFs and average TKEˉ\bar{TKE} spectra are found to compare reasonably nicely with the experimental data, favoring asymmetric mass distributions. The LPs emission cross section is shown to depend strongly on the type of emitted particles and their multiplicities

    An Extension of Analysis of Solar-Heated Thermal Wadis to Support Extended-Duration Lunar Exploration

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    The realization of the renewed exploration of the Moon presents many technical challenges; among them is the survival of lunar surface assets during periods of darkness when the lunar environment is very cold. Thermal wadis are engineered sources of stored solar energy using modified lunar regolith as a thermal storage mass that can supply energy to protect lightweight robotic rovers or other assets during the lunar night. This paper describes an extension of an earlier analysis of performance of thermal wadis based on the known solar illumination of the Moon and estimates of producible thermal properties of modified lunar regolith. The current analysis has been performed for the lunar equatorial region and validates the formerly used 1-D model by comparison of predictions to those obtained from 2-D and 3-D computations. It includes the effects of a thin dust layer covering the surface of the wadi, and incorporating either water as a phase-change material or aluminum stakes as a high thermal conductivity material into the regolith. The calculations indicate that thermal wadis can provide the desired thermal energy and temperature control for the survival of rovers or other equipment during periods of darkness

    Emission of intermediate mass fragments from hot 116^{116}Ba∗^* formed in low-energy 58^{58}Ni+58^{58}Ni reaction

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    The complex fragments (or intermediate mass fragments) observed in the low-energy 58^{58}Ni+58^{58}Ni→116\to ^{116}Ba∗^* reaction, are studied within the dynamical cluster decay model for s-wave with the use of the temperature-dependent liquid drop, Coulomb and proximity energies. The important result is that, due to the temperature effects in liquid drop energy, the explicit preference for α\alpha-like fragments is washed out, though the 12^{12}C (or the complementary 104^{104}Sn) decay is still predicted to be one of the most probable α\alpha-nucleus decay for this reaction. The production rates for non-α\alpha like intermediate mass fragments (IMFs) are now higher and the light particle production is shown to accompany the IMFs at all incident energies, without involving any statistical evaporation process in the model. The comparisons between the experimental data and the (s-wave) calculations for IMFs production cross sections are rather satisfactory and the contributions from other ℓ\ell-waves need to be added for a further improvement of these comparisons and for calculations of the total kinetic energies of fragments.Comment: 22 pages, 15 figure

    Utjecaj superdezintegratora na oslobađanje efavirenca iz tableta

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    Efavirenz (EFV) tablets of different doses were prepared by a wet granulation process using different superdisintegrants such as crosscarmellose sodium (CCS), sodium starch glycollate (SSG) and crosspovidone (CP) to evaluate the role of different disintegrants on the in vitro release of EFV. Further, the mode of addition of disintegrants on EFV dissolution from tablets containing 600 mg of the drug was evaluated by incorporating the disintegrant extragranularly (EG), intragranularly (IG) or distributing them equally (IG and EG). In vitro dissolution of the prepared tablets was conducted using the recommended medium and a dissolution medium developed in-house, which had the propensity to discriminate between the formulations. The t50 and t80 values were indicative of the fact that drug release was faster from tablet formulations containing CP. CP was able to release the drug faster than the other two disintegrants in both dissolution media and the drug release was unaffected by the mode of CP addition.U radu je opisana priprava tableta s različitim dozama efavirenca (EFV) metodom vlaĆŸne granulacije. Za tabletiranje koriĆĄteni su različiti superdezintegratori, poput natrijeve kroskarameloze (CCS), natrijeva ĆĄkrobnog glikolata (SSG) i krospovidona (CP), kako bi se procijenio utjecaj vrste i načina dodavanja dezintegratora na oslobađanje EFV in vitro. U tu svrhu pripravljene su tablete sa 600 mg EFV, a dezintegrator je dodavan ekstragranularno (EG), intragranularno (IG) ili je bio podjednako rasprĆĄen (IG i EG). In vitro oslobađanje praćeno je u preporučenom mediju i mediju izrađenom u naĆĄem laboratoriju kako bi se uočila razlika između formulacija. Vrijednosti t50 i t80 ukazuju na to da je oslobađanje lijeka brĆŸe iz formulacija koje sadrĆŸe CP u oba medija. Način dodavanja CP nema utjecaj na oslobađanje lijeka, osim za CCS, gdje se ekstragranularno dodavanje pokazalo povoljnijim

    Targeted therapy for high-grade glioma with the TGF-ÎČ2 inhibitor trabedersen: results of a randomized and controlled phase IIb study

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    This randomized, open-label, active-controlled, dose-finding phase IIb study evaluated the efficacy and safety of trabedersen (AP 12009) administered intratumorally by convection-enhanced delivery compared with standard chemotherapy in patients with recurrent/refractory high-grade glioma. One hundred and forty-five patients with central reference histopathology of recurrent/refractory glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA) were randomly assigned to receive trabedersen at doses of 10 or 80 ”M or standard chemotherapy (temozolomide or procarbazine/lomustine/vincristine). Primary endpoint was 6-month tumor control rate, and secondary endpoints included response at further timepoints, survival, and safety. Six-month tumor control rates were not significantly different in the entire study population (AA and GBM). Prespecified AA subgroup analysis showed a significant benefit regarding the 14-month tumor control rate for 10 ”M trabedersen vs chemotherapy (p= .0032). The 2-year survival rate had a trend for superiority for 10 ”M trabedersen vs chemotherapy (p = .10). Median survival for 10 ”M trabedersen was 39.1 months compared with 35.2 months for 80 ”M trabedersen and 21.7 months for chemotherapy (not significant). In GBM patients, response and survival results were comparable among the 3 arms. Exploratory analysis on GBM patients aged ≀55 years with Karnofsky performance status >80% at baseline indicated a 3-fold survival at 2 and 3 years for 10 ”M trabedersen vs chemotherapy. The frequency of patients with related or possibly drug-related adverse events was higher with standard chemotherapy (64%) than with 80 ”M trabedersen (43%) and 10 ”M trabedersen (27%). Superior efficacy and safety for 10 ”M trabedersen over 80 ”M trabedersen and chemotherapy and positive risk–benefit assessment suggest it as the optimal dose for further clinical development in high-grade glioma

    Thyroid papillary carcinoma arising in ectopic thyroid tissue within a neck branchial cyst

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    BACKGROUND: Thyroid gland derives from one median anlage at the base of the tongue, and from the two fourth branchial pouches. A number of anomalies may occur during their migration. These can be in form of ectopic tissues, which are frequently found along the course of thyroglossal duct and rarely in other sites, many of these may develop same diseases as the thyroid gland. CASE PRESENTATION: A 36-years-old female presented with a 3 month history of left side neck mass. The mass disappeared following aspiration of brown colored fluid, which on cytological examination showed cells with nuclear irregularities that warranted the resection of the lesion. The histology demonstrated a thyroid papillary carcinoma arising within the branchial cyst. Thereafter, the patient underwent a total thyroidectomy with central lymph nodes dissection. Histology showed a multifocal papillary carcinoma with central lymph nodes metastases. Only four cases of primary thyroid carcinomas in neck branchial cyst have been described so far. CONCLUSION: In a lateral cystic neck mass, although rare, occurrence of ectopic thyroid tissue and presence of a papillary thyroid carcinoma should be kept in mind
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