Effetto doppler ed applicazioni astrofisiche

L’effetto doppler fu scoperto dall'austriaco Christian Johann Doppler che nel 1842 fece una pubblicazione, affermando che un oggetto luminoso deve cambiare colore se posto in moto rispetto ad un osservatore. Infatti notò, sfruttando un vagone con alcuni musicisti sopra, come il suono variasse in base al moto relativo tra vagone ed osservatore. Un'analisi più dettagliata mostrò che un ascoltatore in moto verso una sorgente sonora ferma rispetto al mezzo di trasmissione, riceve un suono di frequenza maggiore rispetto a quello che ascolterebbe se anche lui fosse a riposo. Viceversa la frequenza è minore se l'ascoltatore si allontana dalla sorgente. Fenomeni analoghi si manifestano se la sorgente si muove rispetto al mezzo di trasmissione mentre l’ascoltatore resta fermo. Oggi sappiamo che questo fenomeno è verificato per qualsiasi tipo di onda meccanica

Vitamin C Against Cancer

The selective anticancer properties of vitamin C are known since at least four decades. However, only recently in vitro studies have shown that vitamin C, in high enough concentrations, can efficiently and selectively kill a number of different human tumor cell lines, and these data have been confirmed in experimental animal tumor models. The first human clinical trials revealed that high doses of vitamin C administered by intravenous injection are not only very well tolerated but also substantially improve the quality of life of patients with clinically advanced cancer. However, the clinical evidence of the effectiveness of vitamin C in fighting off cancer is still controversial. The present chapter outlines the importance of vitamin C for a number of physiological functions, within the human body, and shows that there is a solid rationale for its use in the routine treatment of cancer, either alone or in combination with conventional treatment

The cure from nature: the extraordinary anticancer properties of Ascorbate (Vitamin C)

The anticancer properties of Vitamin C (ascorbic acid o sodium ascorbate) are known since at least four decades, However, being a cheap and "natural" product, Vitamin C is not patentable and therefore has never been developed as an anticancer molecule. Recent in vitro investigations have confirmed the extraordinary antitumor properties of high doses of Vitamin C (sodium ascorbate), particularly when administered by the intravenous route, and phase I/II randomized, controlled clinical trials have been started to verify its anticancer properties in vivo. Unfortunately, the controlled clinical trials performed so far, do not confirm the extraordinary results obtained with Vitamin C (sodium ascorbate) in vitro. However, this may depend on a number of different factors, such as the pharmaceutical preparation (Sodium ascorbate may be more suitable than buffered ascorbic acid), the schedule of administration (slow infusion better than rapid infusion), tumor tissue oxygenation (Cancer tissue oxygenation is lower that oxygenation of tumor cell lines, in vitro), etc., which deserve further in depth investigation. Even with these limitations, Vitamin C (sodium ascorbate) in high doses, administered by intravenous route, beyond being extremely effective in vitro, against a number of human tumor cell lines, is safe, has minimal contraindications, improves the quality of life of patients, and is highly selective for cancer cells. The Authors discuss these important aspects and suggest possible solutions to improve the in vivo anticancer effects of Vitamin C (sodium ascorbate)

High Doses of Vitamin C and Leukemia: In Vitro Update

Vitamin C (ascorbic acid) is an essential nutrient with a number of beneficial effects on the human body. Although the majority of mammals can synthesize their own Vitamin C, humans and a few other species, do not produce it and depend on dietary sources for their Vitamin C supply. Among its many effects on cell function and metabolism, Vitamin C has shown, in vitro, a powerful anticancer effect against a number of human tumor cell lines, including myeloid leukemia. There are many different mechanistic explanations for the anticancer/anti-leukemic effects of Vitamin C and the aim of the present review is to illustrate these mechanisms, showing the results of some preliminary in vitro investigations, and outlining their potential clinical relevance

Endocrine Disrupting Chemicals: Effects on Endocrine Glands

In recent years, endocrine disrupting chemicals have gained interest in human physiopathology and more and more studies aimed to explain how these chemicals compounds affect endocrine system. In human populations, the majority of the studies point toward an association between exposure to endocrine disrupting chemicals and the disorders affecting endocrine axis. A great number of endocrine disrupting chemicals seem to be able to interfere with the physiology of hypothalamus-pituitary-gonadal axis; however, every endocrine axis may be a target for each EDCs and their action is not limited to a single axis or organ. Several compounds may also have a negative impact on energy metabolic homeostasis altering adipose tissue and promoting obesity, metabolic syndrome, and diabetes. Different mechanism have been proposed to explain these associations but their complexity together with the degree of occupational or environmental exposure, the low standardization of the studies, and the presence of confounding factors have prevented to establish causal relationship between the endocrine disorders and exposure to specific toxicants so far. This manuscript aims to review the state of art of scientific literature regarding the effects of endocrine-disrupting chemicals (EDCs) on endocrine system

Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery

Peer reviewe

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

I due decenni dell'innovazione Made in China [Two decades of Made in China innnovation]

Almost ten years after the launch of the SciTech Guideline, between the end of the 12th five-year plan (2011-2015) and the beginning of the 13th (2016-2020), the Chinese government has issued the "Made in China 2025" plan (MiC 2025). It is the first out of three plans being part of a wider initiative having the aim of making China a manufacturing power within 2049, to coincide with the 100th anniversary of the foundation of the People's Republic of China. Even if the Chinese planning have been considering innovation and technology as two pillars since the initial years of the Republic, there is a new pervasiveness in the planning efforts. However, differently from the past, these efforts cannot benefit from a positive juncture. The aim of the present work is to trace a first balance of the innovative activity in China, concomitantly with this turning point in policy, analysing a set of synthetic indicators derived from the qualitative-quantitative objectives included in the SciTech Guideline e in the subsequent five-year plans. More specifically, by means of Chinese and international sources, this article does not aim at evaluating, but at deriving a series of stylised facts on innovation in China and at providing some insights for a further discussion on two decades: the one that has just finished and, most of all, the one that has just begun

Do informal institutions matter for the economic resilience of European regions? A study of the post-2008 shock

This paper investigates the relationship between informal institutions and resilience across EU regions in the years following the 2008 Great Recession. By using voluntary work as a proxy for informal institutions, we analyse its association with regional resilience over two different periods: the resistance phase (2008–2010) and the recovery phase (2010–2013). Overall, we find robust evidence that voluntary work is positively associated with greater regional resilience. Our results also show that there is a relation between voluntary work and formal institutions, represented by welfare state models. Overall, the effect of voluntary work is always positive for strong welfare states, but its effect is mitigated by the presence of public provisions. Additionally, in regions with a relatively weaker institutional context, informal institutions retain their positive effect. However, in this context, informal institutions appear to take more time to deploy their effects, but their positive impact on regional labour market recovery is even stronger than in other welfare regimes, probably due to the poor public support that characterises this welfare system