Water (H2O) has a simple composition, but its dizzyingly interconnected hydrogen-bonded networks make structural characterizations challenging. In particular, the organization of water surfaces—a region critical to processes in cell biology and atmospheric chemistry—has caused profound disagreements among scientists.
Figure 1: A ‘snapshot’ from a molecular dynamic simulation reveals that water molecules align at air–water interfaces as coordinated pairs linked by hydrogen bonds. Copyright : 2012 RIKEN
Now, Tahei Tahara and colleagues from the RIKEN Advanced Science Institute in Wako, in collaboration with researchers in Japan and Europe, have uncovered the presence of strongly bonded water pairs at the air–water interface1, rather than previously hypothesized ‘ice-like’ surface structures.
Observing surface water molecules, just a few monolayers thick, requires special experimental techniques that prevent interference by more plentiful bulk particles. One such approach is called vibrational sum frequency generation (VSFG), a laser-based method that selectively vibrates interfacial molecules. Previous VSFG measurements of surface water showed two vibrations that resemble signals recorded from bulk ice and liquid water states. Some scientists have proposed that these vibrations correspond to a partially disordered mix of liquid and four-coordinated ice-like surface structures—a theory at odds with thermodynamic evidence.
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy