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Effect of varied music applications in cycle ergometry
This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel UniversityThe aim of this research programme was to investigate the effects of different music applications: The differentiated exposure of music and the synchronous application of music. In Study 1, participants completed a series of 10-km cycling time trials under four single-blinded conditions: No-music control, music 0-10 km (M1), music 0-5 km (M2), and music 5-10 km (M3). The largest performance gains were noticed under M1, followed by M3, when compared to control, while the most positive psychological response was observed only in M3. Study 2 further examined the notion of differentiated music exposure by incorporating both quantitative and qualitative modes of inquiry. In addition, participants were given foreknowledge of the experimental conditions. Although no performance gains were found across conditions, M3 significantly reduced perceived exertion and prevented affective decline. Qualitative findings suggest that prolonged exposure to music may have negative psychological and psychophysical consequences. The last study contrasted the effects of synchronous and asynchronous application of music in a 6-min submaximal cycling task. Synchronous music was more effective than asynchronous music in terms of reducing perceptions of exertion and increasing subjective arousal. Although no changes in oxygen uptake were found across conditions, auditory-motor synchronisation appeared to reduce heart rate. The contribution of this thesis is twofold. Firstly, the provision of music in the latter stages of a task appears to have significant psychological and psychophysical benefits when compared against constant music exposure. Secondly, more positive effects, in terms of perceived exertion and subjective arousal, are observed when music is applied synchronously compared to asynchronously; this suggests a need for a separate conceptual framework for the application of synchronous music
Assessing the effects of honeypots on cyber-attackers
A honeypot is a non-production system, design to interact with cyber-attackers to collect intelligence on attack techniques and behaviors. While the security community is reaping fruits of this collection tool, the hacker community is increasingly aware of this technology. In response, they develop anti-honeypot technology to detect and avoid honeypots. Prior to the discovery of newer intelligence collection tools, we need to maintain the relevancy of honeypot. Since the development of anti-honeypot technology indicates the deterrent effect of honeypot, we can capitalize on this deterrent effect to develop fake honeypot. Fake honeypot is real production system with deterring characteristics of honeypot that induces the avoidance behavior of cyber-attackers. Fake honeypots will provide operators with workable production systems under obfuscation of deterring honeypot when deployed in hostile information environment. Deployed in a midst of real honeynets, it will confuse and delay cyber-attackers. To understand the effects of honeypot on cyber-attackers to design fake honeypot, we exposed a tightly secured, self-contained virtual honeypot to the Internet over a period of 28 days. We conclude that it is able to withstand the duration of exposure without compromise. The metrics pertaining to the size of last packet suggested departure of cyber-attackers during reconnaissance.http://archive.org/details/assessingeffects109452468Approved for public release; distribution is unlimited
Pengaruh Penambahan Sabut Kelapa Terhadap Stabilitas Campuran Aspal Emulsi Dingin
Di Indonesia penggunaan aspal emulsi sebagai bahan dasar aspal dalam pekerasan lentur masih sangat jarang dijumpai. Hal ini mengakibatkan sedikitnya penelitian tentang aspal emulsi. Untuk itu dibutuhkan penelitian lebih lanjut tentang aspal emulsi. Salah satu hasil alam yang berpotensi dapat digunakan sebagai bahan tambahan pada aspal adalah serabut yang berasal dari buah kelapa. Dalam penelitian ini, sabut kelapa dijadikan sebagai bahan tambahan pada Campuran Aspal Emulsi Dingin (CAED). Sabut kelapa dipotong dan dibersihkan terlebih dahulu sebelum dicampurkan pada CAED. Kadar sabut kelapa yang dipakai beriksar antara 0,50 % - 1,50 % dari total berat aspal dengan panjang berkisar ± 5 mm. Pengujian awal dilakukan dengan pemeriksaan terhadap material yang akan dipakai dalam membuat benda uji. Pemeriksaan terhadap material dilakukan untuk mengetahui apakah material telah memenuhi spesifikasi apakah dapat digunakan sebagai bahan campuran dalam pembuatan benda uji. Pengujian Marshall dilakukan pada CAED dengan sabut kelapa dan tanpa sabut kelapa pada umur 0 hari dan 7 hari. Dari penelitian ini, didapatkan hasil bahwa kadar sabut kelapa optimum yang dapat ditambahkan pada CAED adalah sebesar 0,50 % dari total berat aspal pada umur 7 hari
A cytotoxic and cytostatic gold(III) corrole
We have synthesized and characterized a water-soluble gold(III) corrole (1-Au) that is highly toxic to cisplatin-resistant cancer cells. Relative to its 1-Ga analogue, axial ligands bind only weakly to 1-Au, which likely accounts for its lower affinity for human serum albumin (HSA). We suggest that the cytotoxicity of 1-Au may be related to this lower HSA affinity
Cellular uptake and anticancer activity of carboxylated gallium corroles
We report derivatives of gallium(III) tris(pentafluorophenyl)corrole, 1 [Ga(tpfc)], with either sulfonic (2) or carboxylic acids (3, 4) as macrocyclic ring substituents: the aminocaproate derivative, 3 [Ga(ACtpfc)], demonstrated high cytotoxic activity against all NCI60 cell lines derived from nine tumor types and confirmed very high toxicity against melanoma cells, specifically the LOX IMVI and SK-MEL-28 cell lines. The toxicities of 1, 2, 3, and 4 [Ga(3-ctpfc)] toward prostate (DU-145), melanoma (SK-MEL-28), breast (MDA-MB-231), and ovarian (OVCAR-3) cancer cells revealed a dependence on the ring substituent: IC_(50) values ranged from 4.8 to >200 µM; and they correlated with the rates of uptake, extent of intracellular accumulation, and lipophilicity. Carboxylated corroles 3 and 4, which exhibited about 10-fold lower IC_(50) values (> 3 > 2 >> 1 (intracellular accumulation of gallium corroles was fastest in melanoma cells). We conclude that carboxylated gallium corroles are promising chemotherapeutics with the advantage that they also can be used for tumor imaging
Differential Cytostatic and Cytotoxic Action of Metallocorroles against Human Cancer Cells: Potential Platforms for Anticancer Drug Development
A gallium(III)-substituted amphiphilic corrole noncovalently associated with a targeting protein was previously found by us to confer promising cytotoxic and antitumor activities against a breast cancer cell line and a mouse xenograft breast cancer model. To further explore potential anticancer applications, the cytostatic and cytotoxic properties of six nontargeted metallocorroles were evaluated against seven human cancer cell lines. Results indicated that toxicity toward human cancer cells depended on the metal ion as well as corrole functional group substitution. Ga(III)-substituted metallocorrole 1-Ga inhibited proliferation of breast (MDA-MB-231), melanoma (SK-MEL-28), and ovarian (OVCAR-3) cancer cells primarily by arrest of DNA replication, whereas 2-Mn displayed both cytostatic and cytotoxic properties. Confocal microscopy revealed extensive uptake of 1-Ga into the cytoplasm of melanoma and ovarian cancer cells, while prostate cancer cells (DU-145) displayed extensive nuclear localization. The localization of 1-Ga to the nucleus in DU-145 cells was exploited to achieve a 3-fold enhancement in the IC_(50) of doxorubicin upon coadministration. Time–course studies showed that over 90% of melanoma cells incubated with 30 μM 1-Ga internalized metallocorrole after 15 min. Cellular uptake of 1-Ga and 1-Al was fastest and most efficient in melanoma, followed by prostate and ovarian cancer cells. Cell cycle analyses revealed that bis-sulfonated corroles containing Al(III), Ga(III), and Mn(III) induced late M phase arrest in several different cancer cell lines, a feature that could be developed for potential therapeutic benefit
Psychophysiological effects of synchronous versus asynchronous music during cycling
"This is a non-final version of an article published in final form in (https://journals.lww.com/acsm-msse/pages/articleviewer.aspx?year=2014&issue=02000&article=00024&type=abstract )"Purpose: Synchronizing movement to a musical beat may reduce the metabolic cost of exercise, but findings to date have been equivocal. Our aim was to examine the degree to which the synchronous application of music moderates the metabolic demands of a cycle ergometer task. Methods: Twenty-three recreationally active men made two laboratory visits. During the first visit, participants completed a maximal incremental ramp test on a cycle ergometer. At the second visit, they completed four randomized 6-min cycling bouts at 90% of ventilatory threshold (control, metronome, synchronous music, and asynchronous music). Main outcome variables were oxygen uptake, HR, ratings of dyspnea and limb discomfort, affective valence, and arousal. Results: No significant differences were evident for oxygen uptake. HR was lower under
the metronome condition (122 T 15 bpm) compared to asynchronous music (124 T 17 bpm) and control (125 T 16 bpm). Limb discomfort was lower while listening to the metronome (2.5 T 1.2) and synchronous music (2.3 T 1.1) compared to control (3.0 T 1.5). Both music conditions, synchronous (1.9 T 1.2) and asynchronous (2.1 T 1.3), elicited more positive affective valence compared to metronome (1.2 T 1.4) and control (1.2 T 1.2), while arousal was higher with synchronous music (3.4 T 0.9) compared to metronome (2.8 T 1.0) and control (2.8 T 0.9). Conclusions: Synchronizing movement to a rhythmic stimulus does not reduce metabolic cost but may lower limb discomfort. Moreover, synchronous music has a stronger effect on limb discomfort and arousal when compared to asynchronous music
Protein-coated corrole nanoparticles for the treatment of prostate cancer cells
Development of novel therapeutic strategies to eradicate malignant tumors is of paramount importance in cancer research. In a recent study, we have introduced a facile protocol for the preparation of corrole-protein nanoparticles (NPs). These NPs consist of a corrole-core coated with protein. We now report that a novel lipophilic corrole, (2)Ga, delivered as human serum albumin (HSA)-coated NPs, displayed antineoplastic activity towards human prostate cancer DU-145 cells. Cryo-TEM analysis of these NPs revealed an average diameter of 50.2 ± 8.1 nm with a spherical architecture exhibiting low polydispersity. In vitro cellular uptake of (2)Ga/albumin NPs was attributable to rapid internalization of the corrole through ligand binding-dependent extracellular release and intercalation of the corrole cargo into the lipid bilayer of the plasma membrane. This finding is in contrast with a previously reported study on corrole-protein NPs that displayed cellular uptake via endocytosis. Investigation of the non-light-induced mechanism of action of (2)Ga suggested the induction of necrosis through plasma membrane destabilization, impairment of calcium homeostasis, lysosomal stress and rupture, as well as formation of reactive oxygen species (ROS). (2)Ga also exhibited potent light-induced cytotoxicity through ROS generation. These findings demonstrate a rapid cellular uptake of (2)Ga/protein NPs along with targeted induction of tumor cell necrosis
Protein-coated corrole nanoparticles for the treatment of prostate cancer cells
Development of novel therapeutic strategies to eradicate malignant tumors is of paramount importance in cancer research. In a recent study, we have introduced a facile protocol for the preparation of corrole-protein nanoparticles (NPs). These NPs consist of a corrole-core coated with protein. We now report that a novel lipophilic corrole, (2)Ga, delivered as human serum albumin (HSA)-coated NPs, displayed antineoplastic activity towards human prostate cancer DU-145 cells. Cryo-TEM analysis of these NPs revealed an average diameter of 50.2 ± 8.1 nm with a spherical architecture exhibiting low polydispersity. In vitro cellular uptake of (2)Ga/albumin NPs was attributable to rapid internalization of the corrole through ligand binding-dependent extracellular release and intercalation of the corrole cargo into the lipid bilayer of the plasma membrane. This finding is in contrast with a previously reported study on corrole-protein NPs that displayed cellular uptake via endocytosis. Investigation of the non-light-induced mechanism of action of (2)Ga suggested the induction of necrosis through plasma membrane destabilization, impairment of calcium homeostasis, lysosomal stress and rupture, as well as formation of reactive oxygen species (ROS). (2)Ga also exhibited potent light-induced cytotoxicity through ROS generation. These findings demonstrate a rapid cellular uptake of (2)Ga/protein NPs along with targeted induction of tumor cell necrosis
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