15 research outputs found
On the Schwarzschild Solution: a Review
In this paper the well-known Schwarzschild Solution is discussed. In the first section, by resorting, as usual, to the Einstein Field Equations, a short summary of the conventional derivation is provided. In the second section, we carry out an alternative derivation of the Schwarzschild Metric. The above-mentioned procedureis based upon several noteworthy hypotheses, among which the existence of a further spatial dimension stands out. Initially, we postulate a Universe identifiable with a 4-ball, homogeneously filled with matter, whose radius equates the Schwarzschild Radius. Then, in order to obtain the vacuum field, all the available mass is ideally concentrated in a single point.By imposing a specific condition concerning the measured radius, we deduce a metric that, if subjected to an appropriate parametrization, allows us to finally obtain the Schwarzschild solution
The “Light Clocks” Thought Experiment and the “Fake” Lorentz Transformations
In this paper an alternative version of the well-known “light clocks” experiment is discussed. The so-called Lorentz transformations, backbone of the Special Relativity theory, are herein deduced by resorting to the above-mentioned experiment, albeit with a different meaning. Time dilation and length contraction are not considered as being real phenomena. Time, in fact, is peremptorily postulated as being absolute. Nonetheless, this strong assumption does not imply that instruments and devices of whatever kind, finalized to measure time, are not influenced by motion. In particular, although the “light clock” in the mobile frame ticks, so to say, more slowly than the one at rest, it can be easily shown how no time dilation actually occurs. The apparent length contraction is considered as being nothing but a banal consequence of a deceptive time measurement
A Simplified Introduction to Music Algebra: from the Scale Vectors to the Modal Tensor
In this paper we take a step forward towards the attainment of a formalism that allows to establish a deeper connection between Music and Algebra. Starting from the writing of the Ionian Scale as a Vector, we define the Ionian Modal Tensor. We prove that all the Scales that derive from the Ionian Mode, as well as all the corresponding Seventh Chords, herein considered as being Scalars, can be obtained from the above-mentioned Tensor by resorting to the concepts of Standard Basis and Dot Product.Moreover, by opportunely summing the Vectors of the Standard Basisto each other, we define some interesting Fundamental Vectors such as the "Monk – Powell" Vector and the "Guide Notes" one
Towards a Music Algebra: Fundamental Harmonic Substitutions in Jazz
In this paper the most common harmonic substitutions, at least as far as jazz music is concerned, are unconventionally addressed. The novelty consists in introducing a new method finalized to formally defining and logically applyingall the fundamental harmonic substitutions, by exploiting anunusually rigorous notation. After defining the substitutions and discussing their applicability, we resort to them in order to modify some simple harmonic progressions substantially based upon a banal major turnaround. As explicitly suggested by the title, the modifications are carried out by following an extremely formal line of reasoning: all the logic passages are accurately described by resorting to a notation so similar to the one commonly employed in mathematics and physics, that the harmonic analysis of a song turns out to be de facto comparable to the demonstration of a theorem
Is the EM-Drive a Closed System?
Since its disclosure, the so-called EM-Drive, an apparently reactionless electromagnetic thruster conceived by Roger Shawyer, has simultaneously caused wide scepticism, related to the physical principles that may allow its functioning, and understandable enthusiasm, by virtue of the astonishing scenarios potentially offered by such a device. On the one hand, thrust without exhaust is de facto impossible, unless we deny the Law of Action-Reaction, whose evident violation would result in acknowledging the concrete need for a new Physics; on the other hand, it would appear that opportunely shaped resonant cavities, when fuelled with microwaves, deliver a certain thrust, apparently without a detectable exhaust. In this paper, instead of discussing the validity of the various tests to date independently carried out, speculating about misleading side-effects or inadequate instrumental precision, we simply suppose that the thrust may be an actual phenomenon. Therefore, we try to provide a qualitative explanation to the functioning of the alleged reactionless device, by resorting to a theory elsewhere proposed and herein briefly discussed
Music Algebra: Harmonic Progressions Analysis and CAT (Cataldo Advanced Transformations)
In this article we formally introduce an original method, the purpose of which fundamentally lies in providing musicians with a reliable instrument that may effectively assist them in carrying out, as simply and intuitively as possible, the analysis of whatever chord progression, without resorting to the so-called "modal interchange". Net of a single exception (a routine named "structure reduction"), the whole method is based on a series of harmonic transformations. The above-mentioned transformations, named CAT (the acronym stands for Cataldo Advanced Transformations), turn out to be nothing but inverse chord substitutions characterized by specific conditions and restrictions. The method arises from the analysis of a considerable number of chord progressions, devoting particular (although not exclusive) attention to traditional jazz compositions: in this regard, it is worth highlighting how a significant improvement of CAT has been achieved by conducting an extremely thorough analysis of the so-called LEGO Bricks (public domain harmonic patterns)
Broncalt®, class ii medical device, in patients with chronic relapsed upper airways disease: A survey in clinical practice
Chronic respiratory otorhinolaryngological (ORL) diseases may exacerbate. Broncalt® is a class II Medical Device containing: thermal water (Medesano, PR, Italy), hyaluronic acid, and grapefruit seed extract. It could exert a safe and effective anti-inflammatory, washing, and antimicrobial activity. The current survey, conducted in clinical practice of 84 Italian ORL centers, evaluated its safety and efficacy in the treatment of patients with exacerbated chronic upper airways disease. The 459 (254 males, mean age 44.7 years) patients were evaluated at baseline (T0) and after a 2-week treatment (T1), treated or not-treated with Broncalt®. Signs and symptoms severity were measured by visual analogue scale. Broncalt® significantly, quickly, and safely diminished the clinical features in all sub-groups (p<0.001 for all). In conclusion, Broncalt® is a class II Medical Device able to exert a safe, quick, and effective activity in patients with relapsed chronic ORL disorders. (www.actabiomedica.it)
Broncalt®, class II medical device, in patients with acute upper airways disease: A survey in clinical practice
Inflammation is a common pathogenic mechanism involved in many otorhinolaryngological (ORL) disorders. Broncalt® is a class II Medical Device containing: Thermal water (Medesano, PR, Italy), hyaluronic acid, and grapefruit seed extract. It has been reported that it exerted a safe and effective anti-inflammatory, washing, and antimicrobial activity by virtue of these components. Therefore, the aim of the current survey, conducted in clinical practice of 84 Italian ORL centers, was to evaluate its safety and efficacy in the treatment of patients with acute upper airways disease. The 3,533 (1,797 males, mean age 43.5 years) patients were evaluated at baseline (T0) and after a 2-week treatment (T1) with or without Broncalt®. Signs and symptoms severity were measured by visual analogue scale. Broncalt® significantly and safely diminished the clinical features in all sub-groups (p<0.001 for all). Interestingly, Broncalt® significantly induced a faster symptom relief already within 3 days after the start of the treatment. In conclusion, Broncalt® is a class II Medical Device able to exert a safe and effective activity in patients with acute ORL disorders. (www.actabiomedica.it)
The oral selective oestrogen receptor degrader (SERD) AZD9496 is comparable to fulvestrant in antagonising ER and circumventing endocrine resistance.
BACKGROUND: The oestrogen receptor (ER) is an important therapeutic target in ER-positive (ER+) breast cancer. The selective ER degrader (SERD), fulvestrant, is effective in patients with metastatic breast cancer, but its intramuscular route of administration and low bioavailability are major clinical limitations. METHODS: Here, we studied the pharmacology of a new oral SERD, AZD9496, in a panel of in vitro and in vivo endocrine-sensitive and -resistant breast cancer models. RESULTS: In endocrine-sensitive models, AZD9496 inhibited cell growth and blocked ER activity in the presence or absence of oestrogen. In vivo, in the presence of oestrogen, short-term AZD9496 treatment, like fulvestrant, resulted in tumour growth inhibition and reduced expression of ER-dependent genes. AZD9496 inhibited cell growth in oestrogen deprivation-resistant and tamoxifen-resistant cell lines and xenograft models that retain ER expression. AZD9496 effectively reduced ER levels and ER-induced transcription. Expression analysis of short-term treated tumours showed that AZD9496 potently inhibited classic oestrogen-induced gene transcription, while simultaneously increasing expression of genes negatively regulated by ER, including genes potentially involved in escape pathways of endocrine resistance. CONCLUSIONS: These data suggest that AZD9496 is a potent anti-oestrogen that antagonises and degrades ER with anti-tumour activity in both endocrine-sensitive and endocrine-resistant models
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The oral selective oestrogen receptor degrader (SERD) AZD9496 is comparable to fulvestrant in antagonising ER and circumventing endocrine resistance.
BACKGROUND: The oestrogen receptor (ER) is an important therapeutic target in ER-positive (ER+) breast cancer. The selective ER degrader (SERD), fulvestrant, is effective in patients with metastatic breast cancer, but its intramuscular route of administration and low bioavailability are major clinical limitations. METHODS: Here, we studied the pharmacology of a new oral SERD, AZD9496, in a panel of in vitro and in vivo endocrine-sensitive and -resistant breast cancer models. RESULTS: In endocrine-sensitive models, AZD9496 inhibited cell growth and blocked ER activity in the presence or absence of oestrogen. In vivo, in the presence of oestrogen, short-term AZD9496 treatment, like fulvestrant, resulted in tumour growth inhibition and reduced expression of ER-dependent genes. AZD9496 inhibited cell growth in oestrogen deprivation-resistant and tamoxifen-resistant cell lines and xenograft models that retain ER expression. AZD9496 effectively reduced ER levels and ER-induced transcription. Expression analysis of short-term treated tumours showed that AZD9496 potently inhibited classic oestrogen-induced gene transcription, while simultaneously increasing expression of genes negatively regulated by ER, including genes potentially involved in escape pathways of endocrine resistance. CONCLUSIONS: These data suggest that AZD9496 is a potent anti-oestrogen that antagonises and degrades ER with anti-tumour activity in both endocrine-sensitive and endocrine-resistant models