Articoli filtrati per data: Lunedì, 03 Aprile 2017

Close-up of Polykrilos kofoidii. Photo: Urban Tillmann.

 

Researchers have obtained an unprecedented view of the ‘ballistic’ weaponry of planktonic microbes, including one that can fire projectiles as if wielding a Gatling gun. “We think of plankton as the tiny alphabet soup of the ocean, floating around passively while larger organisms eat it,” says biologist Gregory Gavelis, who lead the study while a researcher at the University of British Columbia (UBC). “But some planktonic microbes, like dinoflagellates, are predators and have developed incredible defensive and prey capture mechanisms.” Until now, how dinoflagellates acquired and fired these projectiles, called extrusomes, was unclear. Gavelis and colleagues studied two types of dinoflagellates: Polykrikos kofoidii and Nematodinium sp. They were able to capture the first 3D views of the microbes’ interior and determined Polykrikos launch a harpoon-like structure to snag their prey, then tow it in. Nematodinium, on the other hand, discharge the contents within a ring of capsules, like a Gatling gun.

Pubblicato in Scienceonline

Concluso a Firenze il 17° Congresso Nazionale dell’Associazione Italiana Psicogeriatria. Relazioni, sentimenti, sfera sessuale al centro dei contributi dinanzi a oltre mille specialisti.

Leo Nahon (già direttore della divisione psichiatrica dell’Ospedale Niguarda di Milano): “In media, il 20-25% degli anziani tra i 75 e gli 85 anni sostiene di aver avuto almeno un rapporto sessuale nell’ultimo anno. Una quota di anziani più ampia del previsto conserva una vita sessuale vera e propria”.

 

ANZIANI: RELAZIONI SESSUALI E AFFETTIVA. Esiste una quota di anziani verosimilmente più ampia del previsto che conserva una vita sessuale vera e propria. “In un editoriale del New England Journal of Medicine del 2015, John Bancroft del Kinsey Institute rilevava che nel gruppo di età fra i 75 e gli 85 anni il 38,5% degli uomini e il 16,7% delle donne riferiva di avere avuto un rapporto sessuale con un partner nell’anno in corso” afferma il prof. Leo Nahon, psichiatra, già direttore della divisione psichiatrica dell’Ospedale Niguarda di Milano. Sono più gli uomini a ricercare il piacere del sesso: per ogni due donne ci sono 3 uomini pronti a vivere questa esperienza appagante. Una curiosità, che lascia intendere come gli uomini ricerchino partner spesso più giovani. Per sessualità non si intende necessariamente il rapporto sessuale completo, ma anche altre forme di erotismo sessuale che gli anziani possono trovare. “Tuttavia, in ambito medico e anche specialistico, l’argomento della sessualità non viene messo tra gli elementi più rilevanti” dichiara ancora Nahon. “In altri termini, né il medico di base né lo specialista, quando si trovano di fronte un ultra 70enne, indagano sul tema della sessualità, a meno che non sia lo stesso paziente a sollevare la questione”.

Pubblicato in Scienceonline

 

A new study demonstrates that gender dysphoria in individuals with coexisting psychotic disorders can be adequately diagnosed and safely treated with gender affirming psychological, endocrine, and surgical therapies. The study is published in LGBT Health, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free on the LGBT Health website until May 3, 2017. In this novel and important report, Julia Meijer, MD, PhD, Guus Eeckhout, MD, Roy van Vlerken, MD, and Annelou de Vries, MD, PhD, VU University Medical Center, Amsterdam, The Netherlands, describe a small series of case studies involving transgender men and women ages 29-57 years diagnosed with gender dysphoria and schizophrenia-related disorders who underwent gender affirmative treatment with a minimum follow-up of 3 years.

Pubblicato in Scienceonline
Lunedì, 03 Aprile 2017 11:07

The dynamic surface tension of water

The release of a water droplet. Image: I.M. Hauner et al.


The surface tension of a liquid is a measure of the cohesive forces that hold the molecules together. It is responsible for a water drop assuming a spherical shape and for the effects of surfactants to produce bubbles and foams. The value of the surface tension of water at room temperature is known accurately to four significant figures and is recommended as a standard for the calibration of other devices. New research in which Ines Hauner and Daniel Bonn (Institute of Physics) are involved now shows that this value is not as universal as previously believed.

Pubblicato in Scienceonline

Osteoblast-cells of a mouse growing on 3D matrices and developed from the waste of agri-food industry (Author: Milagros Ramos, Ángeles Martín, Malcolm Yates and Violeta Zurdo (CTB-UPM y CSIC).

 

Researchers from UPM and CSIC have employed waste from the agri-food industry to develop biomaterials that are able to act as matrices to regenerate bone and cartilage tissues, which is of great interest for the treatment of diseases related to aging. A team of researchers from the Centre for Biomedical Technology at Universidad Politécnica de Madrid (CTB-UPM), in collaboration with Instituto de Ciencia de Materiales (ICMM-CSIC) and Institute of Catalysis and Petrochemistry (ICP-CSIC) from Spanish Council for Scientific Research (CSIC), have produced biocompatible materials from waste of the agri-food industry, specifically from the apple pomace resulting from the juice production.

Pubblicato in Scienceonline

 

Research shows surprising conclusions about fish numbers

 

We're all familiar with the idea of extreme events. Meteorologists keep us up to date on hurricanes, floods and high temperatures. Economists watch the stock market for signs of crashes or rallies. Researchers spend a lot of time trying to better predict these events, yet are often surprised by the outcomes. According to a new study in the journal Limnology & Oceanography Letters, when it comes to nature's extremes, nothing seems to beat what happens underwater. Scientists at the National Science Foundation (NSF) North Temperate Lakes Long-Term Ecological Research (LTER) site -- one of 28 NSF LTER sites -- are routinely measuring everything from water temperature to nutrient concentrations to fish populations in Wisconsin lakes.

Pubblicato in Scienceonline

 

Every tenth employee increases their alcohol consumption to risky levels at the time of retirement from full-time employment. However, the increase seems to be temporary as risky drinking often decreases during the retirement. For most pensioners, alcohol consumption remains below the risk levels before and after retirement. The results of the new Finnish study were published in the esteemed Addiction journal. Of retiring employees, 12 percent increased their risky drinking at the time of retirement. However, for most people, there was no change in risky level alcohol consumption around the time of retirement: 81 percent sustained healthy drinking during the follow-up, and in 7 percent of the participants risky drinking was constant, although they experienced a slow decline in risky level alcohol consumption after retirement. In the study, the levels for risky drinking were 24 units per week for men and 16 units for women, or passing out due to extreme alcohol consumption.

Pubblicato in Scienceonline

Polydom deficient mouse shows severe edema in skin and thoracic cavity (right). Wild-type mouse embryo is shown in left panel.

 

Lymphatic vessels form a circulatory system that plays an important role in controlling the amount of fluid in tissues, and allowing the immune system to identify and target threats. When the lymphatic system malfunctions, fluid accumulates in tissues, producing a condition known as edema. This can be fatal; for example, lung edema can cause respiratory arrest. The molecular mechanisms underlying lymphatic system development are not fully understood, with particular uncertainty surrounding the later stages of development, in which the primitive system is remodeled to produce a mature, functional lymphatic vasculature.

Pubblicato in Scienceonline

 

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