Explicit infiltration equations and the Lambert W-function

The Green and Ampt infiltration formula, as well as the Talsma and Parlange formula, are two-parameter equations that are both expressible in terms of Lambert W-functions. These representations are used to derive explicit, simple and accurate approximations for each case. The two infiltration formulas are limiting cases that can be deduced from an existing three-parameter infiltration equation, the third parameter allowing for interpolation between the limiting cases. Besides the limiting cases, there is another case for which the three-parameter infiltration equation yields an exact solution. The three- parameter equation can be solved by fixed-point iteration, a scheme which can be exploited to obtain a sequence of increasingly complex explicit infiltration equations. For routine use, a simple, explicit approximation to the three- parameter infiltration equation is derived. This approximation eliminates the need to iterate for most practical circumstances

Pick your carats: nanoparticles of gold–silver–copper alloy produced in vivo

Abstract Engineered gold nanoparticle catalysts containing a mixture of metals enable enhanced specificity and reactivity. We report the synthesis by plants of mixed metal nanoparticles suggesting the possibility of using plants to produce catalysts of specific composition, perhaps even those difficult to synthesise by traditional methods. The nanoparticles contain Au, Ag and Cu as an alloy. The structure and composition are confirmed by scanning transmission electron microscopy (STEM) and energy dispersive X-ray analysis (EDX)

Octopus-inspired adhesive skins for intelligent and rapidly switchable underwater adhesion

The octopus couples controllable adhesives with intricately embedded sensing, processing, and control to manipulate underwater objects. Current synthetic adhesive–based manipulators are typically manually operated without sensing or control and can be slow to activate and release adhesion, which limits system-level manipulation. Here, we couple switchable, octopus-inspired adhesives with embedded sensing, processing, and control for robust underwater manipulation. Adhesion strength is switched over 450× from the ON to OFF state in \u3c50 ms over many cycles with an actively controlled membrane. Systematic design of adhesive geometry enables adherence to nonideal surfaces with low preload and independent control of adhesive strength and adhesive toughness for strong and reliable attachment and easy release. Our bio-inspired nervous system detects objects and autonomously triggers the switchable adhesives. This is implemented into a wearable glove where an array of adhesives and sensors creates a biomimetic adhesive skin to manipulate diverse underwater objects

Awareness and use of intertrochanteric osteotomies in current clinical practice. An international survey

Current literature shows that intertrochanteric osteotomies can produce excellent results in selected hip disorders in specific groups of patients. However, it appears that this surgical option is considered an historical one that has no role to play in modern practice. In order to examine current awareness of and views on intertrochanteric osteotomies among international hip surgeons, an online survey was carried out. The survey consisted of a set of questions regarding current clinical practice and awareness of osteotomies. The second part of the survey consisted of five clinical cases and sought to elicit views on preoperative radiological investigations and preferred (surgical) treatments. The results of our survey showed that most of these experts believe that intertrochanteric osteotomies should still be performed in selected cases. Only 56% perform intertrochanteric osteotomies themselves and of those, only 11% perform more than five per year. The responses to the cases show that about 30–40% recommend intertrochanteric osteotomies in young symptomatic patients. This survey shows that the role of intertrochanteric osteotomies is declining in clinical practice

Incorporating lessons from high-input research into a low-margin year

Increased soybean commodity prices in recent years have generated interest in developing high-input systems to increase yield. However, little information exists about the effects of input-intensive, high-yield management on soybean yield and profitability, as well as interactions with basic agronomic practices

Higher risk of 2-year cup revision of ceramic-on-ceramic versus ceramic-on-polyethylene bearing: analysis of 33,454 primary press-fit total hip arthroplasties registered in the Dutch Arthroplasty Register (LROI)

Background and purpose: The influence of bearing on short-term revision in press-fit total hip arthroplasty (THA) remains under-reported. The aim of this study was to describe 2-year cup revision rates of ceramic-on-ceramic (CoC) and ceramic-on-polyethylene (CoPE). Patients and methods: Primary press-fit THAs with one of the three most used cups available with both CoC or CoPE bearing recorded in the Dutch Arthroplasty Register (LROI) were included (2007-2019). Primary outcome was 2-year cup revision for all reasons. Secondary outcomes were: reasons for revision, incidence of different revision procedures and use of both bearings over time. Results: 2-year Kaplan-Meier cup revision rate in 33,454 THAs (12,535 CoC; 20,919 CoPE) showed a higher rate in CoC (0.67% [95% CI, 0.54-0.81]) compared to CoPE (0.44% [95% CI, 0.34-0.54]) (p = 0.004). Correction for confounders (age, gender, cup type, head size) resulted in a hazard ratio (HR) of 0.64 [95%CI, 0.48-0.87] (p = 0.019). Reasons for cup revision differed only by more cup revision due to loosening in CoC (26.2% vs.1 3.2%) (p = 0.030). For aseptic loosening a revision rate of 0.153% [95% CI, 0.075-0.231] was seen in CoC and 0.058% [95%CI 0.019-0.097] in CoPE (p = 0.007). Correction for head size resulted in a HR of 0.475 [95% CI, 0.197-1.141] (p = 0.096). Incidence of different revision procedures did not differ between bearings. Over time the use of CoPE has increased and CoC decreased. Conclusions: A higher 2-year cup revision rate in press-fit THA was observed in CoC compared to CoPE. Cup loosening was the only significantly different reason for revision and seen more often in CoC and mostly aseptic. Future randomised controlled trials need to confirm causality, since the early cup revision data provided has the potential to be useful when choosing the bearing in press-fit THA, when combined with other factors like bone quality and patient and implant characteristics.Orthopaedics, Trauma Surgery and Rehabilitatio

Characterizing Genotype X Management Interactions on Soybean Seed Yield

Increased soybean [Glycine max (L.) Merr.] commodity prices in recent years have generated interest in high-input systems to increase yield. The objective of this study was to evaluate the effects of current, high-yielding cultivars under high- and low-input systems on soybean yield and yield components. Research trials were conducted at 19 locations spanning nine states from 2012 to 2014. At each location, six high-yielding cultivars were grown under three input systems: (i) standard practice (SP, current recommended practices), (ii) high-input treatment consisting of a seed treatment fungicide, insecticide, nematistat, inoculant, and lipo-chitooligosaccharide (LCO); soil-applied N fertilizer; foliar LCO, fertilizer, antioxidant, fungicide and insecticide (SOYA), and (iii) SOYA minus foliar fungicide (SOYA-FF). An individual site-year yield analysis found only 3 of 53 (5.7%) site-years examined had a significant cultivar × input system interaction, suggesting cultivar selection and input system decisions can remain independent. Across all site-years, the SOYA and SOYA-FF treatments yielded 231 (5.5%) and 147 kg ha–1 (3.5%) more than the SP, and input system differences were found among maturity groups. Yield component measurements (seeds m–2, seed mass, early-season and final plant stand, pods plant–1, and seeds pod–1) indicated positive yield responses were due to increased seeds m–2 and seed mass. While both high-input systems increased yield on average, grower return on investment (ROI) would be negative given today’s commodity prices. These results further support the use of integrated pest management principles for making input decisions instead of using prophylactic applications to maximize soybean yield and profitability

Infiltration in soils with a saturated surface

Key Points Analytic description of infiltration in soils Comparison of constant flux and saturated surface infiltration Linking infiltration to soil/water properties An earlier infiltration equation relied on curve fitting of infiltration data for the determination of one of the parameters, which limits its usefulness in practice. This handicap is removed here, and the parameter is now evaluated by linking it directly to soil-water properties. The new predictions of infiltration using this evaluation are quite accurate. Positions and shapes of soil-water profiles are also examined in detail and found to be predicted analytically with great precision