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Around the globe, various types of forest machinery are employed to conduct fully mechanized ground-based timber harvesting. In the Pacific Northwest, the whole-tree harvesting method remains dominant. While machine-integrated sensors provide accurate productivity information in the cut-to-length harvesting method, productivity is more complicated to determine in whole-tree harvesting. This literature review compiles and analyses the existing evidence on productivity studies of feller–bunchers and feller–directors in a systematic manner and identifies the factors influencing machine productivity. The study indicates that most of the previous research was conducted in North America, particularly in Canada. It was also found that a considerable portion of the literature lacked statistical analysis. Piece size, slope, and silvicultural treatment were the most commonly studied productivity-influencing factors among the results. Although there is already a general understanding of the most important factors influencing the productivity of feller–bunchers and feller–directors, there is still a lack of accurate measurement and isolation of individual factors to facilitate accurate productivity prediction. Further research is needed for the development of systems that use integrated sensors capable of estimating machine productivity. Updated productivity models will optimize harvesting operations, identify bottlenecks, and allow for the development of best practices.

The field of climate change communication (CCC) has recently emerged to address the gap between scientific knowledge of climate change and public motivation to respond. Psychologists in this field have offered helpful strategies for improving the effectiveness of CCC, but their empirical research tends to neglect the ethics of CCC. Philosophers have been more attentive to ethical communication, but they tend to focus on its cognitive dimensions and minimize the affective and social dimensions that contribute to effectiveness. As a result, studies that address ethics and effectiveness in tandem are lacking. This chapter fills this gap by recovering insights from Aristotle’s Rhetoric. By situating all communication within an ethical relationship between speaker and auditor, emphasizing the agency and judgement of auditors, and highlighting ways to build trust, Aristotle offers an art of rhetoric that can help climate scientists communicate both ethically and effectively.

Like other immune cells, natural killer (NK) cells show impaired effector functions in the microenvironment of tumors, but little is known on the underlying mechanisms. Since lactate acidosis, a hallmark of malignant tissue, was shown to contribute to suppression of effective antitumor immune responses, we investigated the impact of tissue pH and lactate concentration on NK-cell functions in an aggressive model of endogenously arising B-cell lymphoma. The progressive loss of IFN-γ production by NK cells observed during development of this disease could be ascribed to decreased pH values and lactate accumulation in the microenvironment of growing tumors. Interestingly, IFN-γ expression by lymphoma-derived NK cells could be restored by transfer of these cells into a normal micromilieu. Likewise, systemic alkalization by oral delivery of bicarbonate to lymphoma-developing mice was capable of enhancing IFN-γ expression in NK cells and increasing the NK-cell numbers in the lymphoid organs where tumors were growing. By contrast, NK-cell cytotoxicity was dampened in vivo by tumor-dependent mechanisms that seemed to be different from lactate acidosis and could not be restored in a normal milieu. Most importantly, alkalization and the concomitant IFN-γ upregulation in NK cells were sufficient to significantly delay tumor growth without any other immunotherapy. This effect was strictly dependent on NK cells.

The post-translational modifier ubiquitin is generated exclusively by proteolytic cleavage of precursor proteins. In Saccharomyces cerevisiae, cleavage of the linear precursor proteins releases ubiquitin and the C-terminally fused ribosomal proteins Rpl40 (Ubi1/2 precursor) and Rps31 (Ubi3 precursor), which are part of mature 60S and 40S ribosomal subunits respectively. In this study, we analysed the effects of ubi3 mutations that interfere with cleavage of the ubiquitin-Rps31 fusion protein. Strikingly, the lethal ubi3+P77 mutation, which abolished cleavage almost completely, led to a rapid G1 cell cycle arrest upon genetic depletion of wild-type UBI3. Under these conditions, the otherwise unstable Ubi3+P77 protein was efficiently assembled into translation-competent 40S ribosomal subunits. In contrast to the cleavage-affecting mutations, deletion of the ubiquitin moiety from UBI3 led to a decrease in 40S ribosomal subunits and to the incorporation of the 20S pre-rRNA into polyribosomes. Altogether, our findings provide additional evidence that the initial presence of the ubiquitin moiety of Ubi3 contributes to the efficient production of 40S ribosomal subunits and they suggest that ubiquitin release is a prerequisite for their functional integrity.

Pathogens and nutrients released from on-site sewage systems represent a risk to surface and ground water quality, particularly where there are sensitive receiving waters such as in drinking water catchments. Buffer zones between on-site systems and waterways are one barrier used to protect water quality. The increased time and distance they provide increases the opportunities for the effluent purification functions of the soil to occur. A risk management model is proposed to assess the efficacy of the buffer zones in Sydney's drinking water catchments. The model is the basis for the development of performance based setback distances for on-site systems from waterways, and incorporates stochastic analysis of pathogen and nutrient transport in the environment and consideration of the effluent quality variability from on-site systems. Catchment-scale integration of contaminant transport is employed to facilitate a risk assessment of on-site systems. The risk management model also allows for the impact of on-site system management and maintenance on catchment water quality to be assessed through scenario building and feedback mechanisms.

The Ross operation, introduced more than 30 years ago, has recently undergone several modifications to improve both technical feasibility and results. At the authors' institution, the Ross operation, performed as root replacement in all cases, was commenced in February 1995.A total of 225 patients (177 males, 48 females; mean age 39+/-15 years; range: 2 to 67 years) were operated on up to December 2000. Aortic regurgitation was present in 80 patients, stenosis in 69, and combined disease in 73; prostheses were replaced in three patients. Combined procedures were performed in 51 patients. Nine patients had active endocarditis. Follow up was 98% complete and totaled 471 patient-years.There was no early mortality, and no thromboembolic or hemorrhagic events. Complications included prolonged ventilation in two patients, perioperative myocardial infarction in three, pacemaker implants in three and perioperative bleeding in six. One patient died at 25 months from hemoptysis, and one at five months of unknown cause. In the long term, four patients required reoperation due to autograft regurgitation (one autograft repair, three autograft replacements). Routine aortic annulus support, a lowered threshold in replacing all dilated ascending aorta and keeping the autograft short to the level of the sinotubular junction seems to have prevented further autograft failure. Pulmonary homograft stenosis led to reoperation in one patient. Six patients with elevated gradients are currently under observation. Echocardiography revealed autograft median peak gradients of 5.1+/-2.8 mmHg, pulmonary homograft gradients of 14.2+/-11.5 mmHg, and no significant regurgitation, except in one additional patient with recently diagnosed aortic insufficiency (grade2).Mid-term excellent hemodynamic results, low morbidity and reoperation requirement support the evolved root replacement technique and justify its further utilization.

With the introduction of the maze operation Cox was able to show that the surgical treatment of atrial fibrillation (AF) is feasible. However, the maze operation remains surgically demanding and time-consuming as it requires multiple incisions in both atria. This has led to the development of various modifications. With new ablative technology and the acceptable results of an exclusively left atrial maze procedure in combination with mitral valve surgery, it has become possible to simplify the maze operation radically. Thirty-one patients ( mean age 62.3 years) with chronic or intermittent AF underwent a modified radiofrequency procedure in combination with some other cardiac surgical operation. Mitral valve disease coexisted in 17 patients, aortic valve disease in 9, coronary heart disease in 4 patients and 1 had an atrial septal defect (ASD). After left atriotomy and with the use of the Thermaline radiofrequency ablator probe, bilateral pulmonary vein isolation was carried out. An additional ablation line was directed from the left pulmonary veins to the posterior mitral valve annulus, and finally the left atrial appendage was resected. The complete procedure added an average of only 18.2 minutes to the operation. In the early postoperative course AF or atrial flutter recurred in 12 patients but at discharge only 8 patients (24%) still had an arrhythmia. We concentrated on the first 26 patients of our series who had received a follow-up examination 3 months postoperatively. At discharge 18 of the 26 patients were in sinus rhythm (69,2%), and at 3 months after surgery 23 of 26 patients were in sinus rhythm (88.5%), with recovery of atrial contraction confirmed echocardiographically. Only 4 patients still required medication for arrhythmias. The modified radiofrequency ablation procedure of the left atrium proved to be simple to perform, quick and reliable. It offers the possibility of a surgical cure for AF when performed together with another cardiac operation, and the early results indicate a high rate of success for this simple procedure.