Nitrogenase is the only enzyme that can cleave the strong triple bond inN2. The active site contains a complicated MoFe7S9C cluster. It is believed that itneeds to accept four protons and electrons, forming the E4 state, before it can bind N2.However, there is no consensus on the atomic structure of the E4 state. Experimentalstudies indicate that it should contain two hydride ions bridging two pai

We have investigated the implications of the recent crystallographic findings that the m2-bridging S2B sulfide ligand may reversibly dissociate from the active-site FeMo cluster of nitrogenase. We show with combined quantum mechanical and molecular mechanical (QM/MM) calculations that once S2B has dis- sociated, N2 may bind in that position and can be protonated to two NH3 groups by thermodynamica

Polymer electrolyte fuel cells (PEFCs) have shown a great potential to be used in several applications, e.g., portable, mobile and stationary systems. Each of the mentioned applications demands from PEFCs different operating conditions to perform in the best possible manner. Knowing in detail the behavior of their internal components will help to improve the mechanical and thermal properties of th

Today, just as in the early days of flying, much emphasis is put on the pilot student’s flight training before flying a real commercial aircraft. In the early stages of a pilot student’s education, they must, for example, learn different operating procedures known as flow patterns using very basic tools, such as exhaustive manuals and a so-called paper tiger. In this paper, we present a first desi

BACKGROUND & AIMS: Although colorectal cancer (CRC) screening guidelines acknowledge the need for earlier screening for high-risk individuals, such as those with family history of CRC, there is limited information on how many years earlier these high-risk individuals should be screened; current practice is based on weak evidence. We aimed to provide risk-adapted recommendations on the starting

BACKGROUND: The question of whether having a family history of prostatic borderline or in situ neoplasia (PBISN) is associated with an increased risk of invasive prostate cancer (PCa) or death from PCa remains unanswered. The objective of the current study was to provide an evidence-based risk estimation for the relatives of patients with PBISN.METHODS: Nationwide Swedish family cancer data sets w

Globally, agrifoodsystems are in constant evolution. In such a context, agronomists have the critical task to act as change agents, enabling agricultural innovation and facilitating the transition towards sustainability. Hence, agronomists should develop a new professional mindset that goes beyond the prescribed roles and fixed duties of a bounded professional. However, it is questionable whether

The potential benefit of nonpharmacological adjunctive therapy is not well-studied following major abdominal surgery. The aim of the present study was to investigate transcutaneous electrical nerve stimulation (TENS) as a complementary nonpharmacological analgesia intervention during weaning from epidural analgesia (EDA) after open lower abdominal surgery. Patients were randomized to TENS and sham

Background: Advances in perioperative pediatric care have resulted in an increased number of procedures requiring anesthesia. During anesthesia and surgery, the patient is subjected to factors that affect the circulatory homeostasis, which can influence oxygenation of the brain. Near-infrared spectroscopy (NIRS) is an easy applicable noninvasive method for monitoring of regional tissue oxygenation

Background: Isocapnic hyperventilation (IHV) shortens recovery time after inhalation anaesthesia by increasing ventilation while maintaining a normal airway carbon dioxide (CO2)-level. One way of performing IHV is to infuse CO2 to the inspiratory limb of a breathing circuit during mechanical hyperventilation (HV). In a prospective randomized study, we compared this IHV technique to a standard emer

Background: Isocapnic hyperventilation (IHV) is a method that shortens time to extubation after inhalation anaesthesia using hyperventilation (HV) without lowering airway CO 2 . In a clinical trial on patients undergoing long-duration sevoflurane anaesthesia for major ear–nose–throat (ENT) surgery, we evaluated the utility of a technique for CO 2 delivery (DCO 2 ) to the inspiratory limb of a clo

Background Post-operative cognitive dysfunction (POCD) after non-cardiac surgery is a well known problem in some categories of patients. This study aims to evaluate the influence of auditory evoked potential (AEP)-guided anaesthesia on the requirement for anaesthetic drugs and their influence on POCD. Methods Four hundred and fifty patients aged between 18 and 92 years scheduled for ophthalmic sur

The aim of this study was to evaluate the role of depth of anesthesia on POCD after major ENT surgery and to assess changes in postoperative inflammatory markers in patients undergoing major ENT surgery. Thirty two patients aged 40 to 94 yrs, scheduled for surgery under general anesthesia were randomly assigned to one of two groups. In group A (AEP group) depth of anesthesia (DOA) was measured wit

Introduction: Trauma stress and neuro-inflammation caused by surgery/anaesthesia releases cytokines. This study analysed impact of Auditory Evoked Potential Index (AAI) depth-of-anaesthesia titration on the early plasma IL-6 release after eye surgery under general anaesthesia. Method: This is a subgroup analysis of a prospective randomized study on the effect of auditory evoked potential guided an

Cognitive side-effects such as emergence agitation (EA), postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are not infrequently complicating the postoperative care especially in elderly and fragile patients.The aim of the present survey was to gain insight regarding concern and interest in prevention and treatment strategies for postoperative delirium and dysfunction, and

Emergence agitation following anesthesia in children is not uncommon. It is, although generally self-limiting, associated with both patient and parents distress. We conducted a national survey around the management of behavioral and neurocognitive disturbances after surgery/anesthesia including a case scenario about a child at risk for emergence reaction. Premedication with clonidine or midazolam

Postoperative nausea and vomiting ". the little big problem" after surgery/anaesthesia is still a common side-effect compromising quality of care, delaying discharge and resumption of activities of daily living. A huge number of studies have been conducted in order to identify risk factors, preventive and therapeutic strategies. The Apfel risk score and a risk based multi-modal PONV prophylaxis is