Standard Plating Research Articles

Effect of bath temperature on electroplating of nickel on a copper substrate

ABSTRACT Nickel electroplating is known to be industrially effective for enhancing various substrate properties. In the present work, nickel coatings were developed on copper substrates by electroplating using standard nickel plating solution at various electrolyte bath temperatures ranging from 40 ± 2°C to 60 ± 2°C in steps of 10°C. Energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were used to study the composition, phase structure and morphology of the coatings. The coatings were also analysed for hardness and porosity, and process current efficiency was measured. The electrolyte bath temperature has a profound effect on the nature of the developed nickel coatings, and is observed to have an impact on the surface morphology, crystallographic direction, and hardness, as well as deposition current efficiency.

A diverse range of Phytophthora species from botanical gardens in South Africa, including the novel Clade 5 species, Phytophthora mammiformis sp. nov.

The genus Phytophthora contains many destructive and globally important plant pathogens. In the last decade, targeted sampling efforts have resulted in a dramatic increase in the number of known species, as well as a better understanding of their global distribution. Routine activities undertaken in botanical gardens, combined with great numbers of local and international visitors, place botanical gardens at risk to the accidental introduction and establishment of pathogens such as Phytophthora spp. In this study, the occurrence of Phytophthora was investigated in two botanical gardens in the KwaZulu-Natal Province of South Africa. Symptomatic collar and stem tissues were collected, and root and rhizosphere soil samples were taken from trees exhibiting symptoms of decline. Standard baiting techniques and direct plating of symptomatic tissues revealed the presence of seven species of Phytophthora residing in four phylogenetic clades. Five of these species, P. cinnamomi, P. citrophthora, P. multivora, P. parvispora and the informally designated taxon Phytophthora sp. stellaris were known to be present in South Africa and P. aquimorbida was recorded for the first time. Of these, P. citrophthora represented a novel host-pathogen association causing bleeding cankers on indigenous Celtis africana. A multilocus phylogenetic analysis based on ITS, βtub, cox1 and hsp90 sequences showed the presence of an undescribed species belonging to the Phytophthora ITS Clade 5. This species is described here as Phytophthora mammiformis sp. nov. This study highlights the importance of monitoring botanical gardens for the detection and discovery of pathogens and emphasises their value as sites for the discovery of novel host-pathogen associations. Citation: Paap T, Balocchi F, Burgess TI, Bose T, Wingfield MJ (2024). A diverse range of Phytophthora species from botanical gardens in South Africa, including the novel Clade 5 species, Phytophthora mammiformis sp. nov. Fungal Systematics and Evolution 13: 111-122. doi: 10.3114/fuse.2024.13.05.

Benefits of Rib Fixation Utilizing Low-Cost Materials: A Randomized Pilot Trial

IntroductionSurgical stabilization of rib fractures (SSRF) using standard rib plating systems has become a norm in developed countries. However, the procedure has not garnered much interest in low–middle-income countries, primarily because of the cost. MethodsThis was a single-center pilot randomized trial. Patients with severe rib fractures were randomized into two groups: SSRF and nonoperative management. SSRF arm patients underwent surgical fixation in addition to the tenets of nonoperative management. Low-cost materials like stainless steel wires and braided polyester sutures were used for fracture fixation. The primary outcome was to assess the duration of hospital stay. ResultsTwenty-two patients were randomized, 11 in each arm. Per-protocol analysis showed that the SSRF arm had significantly reduced duration of hospital stay (22.6 ± 19.1 d versus 7.9 ± 5.7 d, P value 0.031), serial pain scores at 48 h and 5 d (median score 5, IQR (3-6) versus median score 7, IQR (6.5-8), P value 0.004 at 48 h and median score 2 IQR (2-3) versus median score 7 IQR (4.5-7) P value 0.0005 at 5 d), significantly reduced need for injectable opioids (9.9 ± 3.8 mg versus 4.4 ± 3.4 mg, P value 0.003) and significantly more ventilator-free days (19.9 ± 8.7 d versus 26.4 ± 3.2 d, P value 0.04). There were no statistically significant differences in the total duration of ICU stay (median number of days 2, IQR 1-4.5 versus median number of days 7, IQR 1-14, P value 0.958), need for tracheostomy (36.4% versus 0%, P value 0.155), and pulmonary and pleural complications. ConclusionsSSRF with low-cost materials may provide benefits similar to standard rib plating systems and can be used safely in resource-poor settings.

Laser assisted electrodeposition of binary metallic alloys from water-based electrolytes: The case of palladium‑platinum

The present work investigates the applicability of laser assisted electrodeposition (LAE) to the plating of binary metallic alloys from aqueous solutions and in absence of any external polarization. PdPt was chosen as prototypical system and the deposition was carried out from phosphate-based electrolytes. The effect of electrolyte formulation and laser parameters on the composition, thickness and physical properties of the alloys was studied. In order to provide more insight on the LAE deposition process of alloys, the electrochemical properties of the electrolytes employed were correlated with the properties of the materials obtained. In analogy with standard alloy plating processes, a clear link between the currents observed for the reduction of the two single metals and the composition/thickness of the coated PdPt layers could be established. Compositionally tunable and continuous PdPt coatings were obtained and their chemical, morphological and mechanical properties were determined. Finally, the possibility to selectively deposit the PdPt alloy was demonstrated by patterning a complex figure.

Lipidomic analysis by LC-MS/MS of wildtype, mutant and VBNC strains of Francisella tularensis LVS.

Francisella tularensis is one of the many bacteria that can enter a viable but nonculturable state (VBNC). The VBNC state acts as an adaptive strategy that allows for long-term survival of bacteria in unfavorable environments. A defining characteristic of VBNC bacteria is a loss of culturability, making VBNC bacteria difficult to detect in the environment using standard plating assays. Failure to identify VBNC bacteria in the food industry or water distribution centers poses a serious risk to human health. Our preliminary data suggests that lipid metabolism plays a role in VBNC adaptation in F. tularensis. To investigate further, genetic deletion mutants have been constructed from two predicted lipid metabolism genes, FTL_1569 (phosphoglycolate phosphatase) and FTL_1570 (phospholipase D family protein). Lipid extracts were collected from wildtype, mutant and VBNC strains of F. tularensis to determine any lipid species associated with the VBNC state. A single-phase lipid extraction method was used to obtain lipids from F. tularensis cultures grown for 24 hours (culturable) and 336 hours (VBNC). Liquid chromatography with tandem mass spectrometry (LC-MS-MS) and the ThermoFisher Compound Discoverer software were utilized for lipid identification, and comparative analyses. Differences in the lipid profile of wildtype, mutant and VBNC strains of F. tularensis have been identified. (Supported by NIH Grant P20GM103434 to the West Virginia IDeA Network for Biomedical Research Excellence)

“Does Hook Type Matter in Articular Distal Radius Fixation? Re. Does Construct Type Matter? A Retrospective Review Comparing Outcomes of Distal Radius Fractures Treated with Standard Volar Plating versus Fragment-specific Fixation”

“Does Hook Type Matter in Articular Distal Radius Fixation? Re. Does Construct Type Matter? A Retrospective Review Comparing Outcomes of Distal Radius Fractures Treated with Standard Volar Plating versus Fragment-specific Fixation”

The Shunt Valve Recession Technique as a Neuroplastic Surgery Adjunct in Complex and High-Risk Shunt Revisions: Technical Note and Case Series.

Ventricular shunting is one of the most common procedures in neurosurgery. However, complications and revisions are frequent. Patients requiring multiple revisions often suffer secondary issues with scalp healing over hardware. Many common ventricular shunt valves have an obligate thickness that creates a visible protrusion and can potentially cause local tissue ischemia and breakdown in the setting of repeated surgery. The authors present a simple technique for recessing the shunt valve into the underlying bone to alleviate protrusion in high-risk cases. Three example cases utilizing this technique are presented. The skull directly underlying the planned valve site is uniformly recessed with a cutting burr several millimeters as desired while maintaining the inner cortical bone layer. The valve is fixed with standard cranial plating hardware. Three patients are reported who underwent shunt valve recession as an adjunct to their shunt revision with neuroplastic surgery assistance. All patients had undergone multiple prior surgeries that had resulted in thin and high-risk fragile scalp. In 1 patient, the prior valve was eroding through the scalp before the described revision. All patients had satisfactory cosmetic outcomes, and there were no revisions in the 2-month follow-up period. Complex and high-risk ventricular shunt patients should be considered for shunt valve recession into the bone to reduce wound-related complications and enhance healing. This is a technically simple, safe, and effective technique to include as a neuroplastic adjunct.

Isolation and Identification of Antibiotic-Susceptible Bacteria from Abattoir Effluent in Port Harcourt, Rivers State, Nigeria

Abattoir environment can become a significant reservoir for antibiotic resistance bacteria, particularly in abattoirs that do not treat their waste before discharge. This study seeks to verify the antibiotics susceptibility profile of bacteria isolated from abattoir wastewater in Port Harcourt, River State, Nigeria. The bacteria were isolated from the wastewater using a standard plating technique. The antibiotics sensitivity pattern of all bacterial isolates was determined by the Kirby-Bauer disk diffusion method. Isolates with high multiple antibiotic resistance (MAR) index (≥0.5) were screened for genes for pathogenicity (icaC, adhesion gene) and antibiotic resistance (QnrA gene). The abattoir wastewaters were contaminated by bacteria resistant to no less than two of the antibiotics experimented with (MAR index range, 0.2-1.0). The isolates were identified as Acinetobacter brisouii, Bacillus altitudinis, Bacillus stratosphericus and Priestia flexa. Among these isolates, 2(50.0%) harboured the QnrA gene while 3(75.0%) harboured the icaC gene. The findings underscore the importance of abattoir wastewater as an environmental flashpoint for antibiotic resistance. Detection of bacteria with multiple antibiotic resistance in abattoir wastewater would inform cautious use of antibiotics, to check the spread of antibiotic resistance emanating from this source.

Influence of Doped Detonation Nanodiamonds on the Physical and Chemical Properties of Electrochemical Chromium Coatings

Chromium deposition process regularities are analyzed in the standard chromium plating electrolytes, with and without detonation nanodiamonds additives modified with boron, phosphorus (DND-boron, phosphorus-DND) at a temperature of 50º to 55ºC while stirring the solution and without. It was studied by method of recording the partial polarization curves the concentration effect of additives DND-boron (in the range of 2,5 ÷ 10 g/l) on the kinetics of the chromate ion partial and full reducing. It has been shown that increasing the concentration of DND-boron leads to inhibition of the reaction Cr (VI) → Cr (III) and Cr polarization curves shift reaction (VI) → Cr (0) to a negative potential on the magnitude of 40-70 mV. While stirring the electrolyte chromium deposition occurs at more positive potentials than in quiescent electrolyte. Dependence of the electrode potential on the current density logarithm in all cases are linear with a slope close to 120 mV, indicating a limiting step of attaching the first electron. Mechanism of deposition of chrome in the presence of boron-DND does not change. Shiny, smooth, uniform coatings are deposited in electrolytes with DND-boron additives. Increased polarization in the chromium precipitation of electrolytes with DND-boron causes a change in precipitation structure, and as a consequence an increase in microhardness of chrome coatings from 955 kgf/mm2 for pure chromium to 1430 kgf/mm2 for chromium with embedded DND-boron nanodiamond particles. Wear resistance is increased: using DND-TAN - 2-3 times compared to standard chrome plating, using DND-phosphorus - in 3 times in comparison with DND-TAN, and using DCS (Si), doped silicon, wear is not detected (under the test conditions).

Medial helical versus straight lateral plating of distal femoral fractures—a biomechanical comparative study

BackgroundDistal femoral fractures are commonly treated with lateral straight plates. However, the lateral approach may not always be desirable, and 180°-helical plates may be an alternative. AimTo investigate the biomechanical competence of 180°-helical plating versus standard straight lateral plating of unstable fractures at the distal femur. MethodsTwelve left artificial femora were instrumented with a 15-hole Locking Compression Plate–Distal Femur, using either 180°-helical plates (group 1) or conventional straight lateral plates (group 2). An unstable distal femoral fracture AO/OTA 33-A3.3 was simulated. All specimens were biomechanically tested under quasi-static and progressively increasing combined cyclic axial and torsional loading in internal rotation until failure. FindingsInitial axial stiffness (N/mm) was significantly higher in group 1 (185.6 ± 50.1) compared to group 2 (56.0 ± 14.4), p < 0.001. Group 1 demonstrated significantly higher initial interfragmentary flexion (°) and significantly lower initial varus/valgus deformation (°) under 500 N static axial compression versus group 2 (2.76 ± 1.02 versus 0.87 ± 0.77 and 4.08 ± 1.49 versus 6.60 ± 0.47), p ≤ 0.005. Shear displacement (mm) under 6 Nm static torsion was significantly higher in group 1 versus group 2 in both internal (1.23 ± 0.28 versus 0.40 ± 0.42) and external (1.21 ± 0.40 versus 0.57 ± 0.33) rotation, p ≤ 0.013. Cycles to failure and failure load (N) (clinical/catastrophic) were significantly higher in group 1 (12,484 ± 2116/13,752 ± 1518 and 1748.4 ± 211.6/1875.2 ± 151.8) compared to group 2 (7853 ± 1262/9727 ± 836 and 1285.3 ± 126.2/1472.7 ± 83.6), p ≤ 0.001. InterpretationAlthough 180°-helical plating using a pre-contoured standard straight lateral plate was associated with higher shear and flexion movements, it demonstrated improved initial axial stability and resistance against varus/valgus deformation compared to straight lateral plating. Moreover, the helical plates were associated with significantly higher endurance to failure. From a biomechanical perspective, 180°-helical plating may be considered as a valuable alternative to standard straight lateral plating of unstable distal femoral fractures.

Substitutional semi-rigid osteosynthesis technique for treatment of unstable pubic symphysis injuries: a biomechanical study

Background/PurposeThe surgical fixation of a symphyseal diastasis in partially or fully unstable pelvic ring injuries is an important element when stabilizing the anterior pelvic ring. Currently, open reduction and internal fixation (ORIF) by means of plating represents the gold standard treatment. Advances in percutaneous fixation techniques have shown improvements in blood loss, surgery time, and scar length. Therefore, this approach should also be adopted for treatment of symphyseal injuries. The technique could be important since failure rates, following ORIF at the symphysis, remain unacceptably high. The aim of this biomechanical study was to assess a semi-rigid fixation technique for treatment of such anterior pelvic ring injuries versus current gold standards of plate osteosynthesis.MethodsAn anterior pelvic ring injury type III APC according to the Young and Burgess classification was simulated in eighteen composite pelvises, assigned to three groups (n = 6) for fixation with either a single plate, two orthogonally positioned plates, or the semi-rigid technique using an endobutton suture implant. Biomechanical testing was performed in a simulated upright standing position under progressively increasing cyclic loading at 2 Hz until failure or over 150,000 cycles. Relative movements between the bone segments were captured by motion tracking.ResultsInitial quasi-static and dynamic stiffness, as well as dynamic stiffness after 100,000 cycles, was not significantly different among the fixation techniques (p ≥ 0.054).). The outcome measures for total displacement after 20,000, 40,000, 60,000, 80,000, and 100,000 cycles were associated with significantly higher values for the suture technique versus double plating (p = 0.025), without further significant differences among the techniques (p ≥ 0.349). Number of cycles to failure and load at failure were highest for double plating (150,000 ± 0/100.0 ± 0.0 N), followed by single plating (132,282 ± 20,465/91.1 ± 10.2 N), and the suture technique (116,088 ± 12,169/83.0 ± 6.1 N), with significantly lower values in the latter compared to the former (p = 0.002) and no further significant differences among the techniques (p ≥ 0.329).ConclusionFrom a biomechanical perspective, the semi-rigid technique for fixation of unstable pubic symphysis injuries demonstrated promising results with moderate to inferior behaviour compared to standard plating techniques regarding stiffness, cycles to failure and load at failure. This knowledge could lay the foundation for realization of further studies with larger sample sizes, focusing on the stabilization of the anterior pelvic ring.

A targeted liquid cultivation method for previously uncultured non-colony forming microbes

A large number of microbes are not able to form colonies using agar-plating methods, which is one of the reasons that cultivation based on solid media leaves the majority of microbial diversity in the environment inaccessible. We developed a new Non-Colony-Forming Liquid Cultivation method (NCFLC) that can selectively isolate non-colony-forming microbes that exclusively grow in liquid culture. The NCFLC method involves physically separating cells using dilution-to-extinction (DTE) cultivation and then selecting those that could not grow on a solid medium. The NCFLC was applied to marine samples from a coastal intertidal zone and soil samples from a forest area, and the results were compared with those from the standard direct plating method (SDP). The NCFLC yielded fastidious bacteria from marine samples such as Acidobacteriota, Epsilonproteobacteria, Oligoflexia , and Verrucomicrobiota . Furthermore, 62% of the isolated strains were potential new species, whereas only 10% were novel species from SDP. From soil samples, isolates belonging to Acidobacteriota and Armatimonadota (which are known as rare species among identified isolates) were exclusively isolated by NCFLC. Colony formation capabilities of isolates cultivated by NCFLC were tested using solid agar plates, among which approximately one-third of the isolates were non-colony-forming, approximately half-formed micro-colonies, and only a minority could form ordinary size colonies. This indicates that the majority of the strains cultivated by NCFLC were previously uncultured microbial species unavailable using the SDP method. The NCFCL method described here can serve as a new approach to accessing the hidden microbial dark matter.

HELICAL PLATING VERSUS STRAIGHT PLATING AND INTRAMEDULLARY NAILING OF PROXIMAL THIRD HUMERAL SHAFT FRACTURES: A BIOMECHANICAL COMPARATIVE STUDY

Proximal humeral shaft fractures are commonly treated with long straight plates or intramedullary nails. Helical plates might overcome the downsides of these techniques as they are able to avoid the radial nerve distally. The aim of this study was to investigate in an artificial bone model: (1) the biomechanical competence of different plate designs and (2) to compare them against the alternative treatment option of intramedullary nails.Twenty-four artificial humeri were assigned in 4 groups and instrumented as follows: group1 (straight 10-hole-PHILOS), group2 (MULTILOCK-nail), group3 (45°-helical-PHILOS) and group4 (90°-helical-PHILOS). An unstable proximal humeral shaft fracture was simulated. Specimens were tested under quasi-static loading in axial compression, internal/external rotation and bending in 4 directions monitored by optical motion tracking.Axial displacement (mm) was significantly lower in group2 (0.1±0.1) compared to all other groups (1: 3.7±0.6; 3: 3.8±0.8; 4: 3.5±0.4), p&lt;0.001. Varus stiffness in group2 (0.8±0.1) was significantly higher compared to groups1+3, p≤0.013 (1: 0.7±0.1; 3: 0.7±0.1; 4: 0.8±0.1). Varus bending (°) was significantly lower in group2 compared to all other groups (p&lt;0.001) and group4 to group1, p=0.022. Flexion stiffness in group1 was significantly higher compared to groups2+4 (p≤0,03) and group4 to group1, p≤0,029 (1: 0.8±0.1; 2: 0.7±0.1; 3: 0.7±0.1; 4: 0.6±0.1). Flexion bending (°) in group4 was higher compared to all other groups (p≤0.024) and lower in group2 compared to groups1+4, p≤0.024. Torsional stiffness remained non significantly different, p≥0.086. Torsional deformation in group2 was significantly higher compared to all other groups, p≤0.017. Shear displacement remained non significantly different, p≥0.112.From a biomechanical perspective, helical plating with 45° and 90° may be considered as a valid alternative fixation technique to standard straight plating of proximal third humeral fractures. Intramedullary nails demonstrated higher axial and bending stiffness as well as lower fracture gap movements during axial loading compared to all plate designs. However, despite similar torsional stiffness they were associated with higher torsional movements during internal/external rotation as compared to all investigated plate designs.

Passenger vehicle interior decontamination by low concentration hydrogen peroxide vapor following a wide area biological contamination incident.

To assess low concentration hydrogen peroxide (LCHP) (H2O2) vapor dispersed with a home humidifier for its ability to decontaminate vehicle interiors contaminated with Bacillus anthracis surrogate Bacillus atrophaeus spores. Efficacy of a vaporized 3% H2O2 solution was evaluated for liquid volumes, on/off vehicle heating, ventilation, and air conditioning (HVAC) system operations, and temperatures that ranged from 5 to 27°C. Survival of the spores was assessed by quantification of remaining viable spores with efficacy quantified in terms of mean log10 reduction. Decontamination efficacy after the 6-day dwell time increased when the 3% H2O2 liquid volume was doubled, increasing from 4-of-10 to 10-of-10 nondetects (zero colonies counted using standard dilution and filter plating) inside the vehicle cabin. Recirculating cabin air through the HVAC system during decontamination decreased efficacy to 6-of-10 non-detects. While no 6-log10 reduction in viable spores was observed on the cabin filter with the cabin filter kept in place, a 6-log10 reduction was achieved after its removal and placement in the cabin during treatment. Results from this study allow for informed decisions on the use of LCHP vapor as an effective decontamination approach for vehicle interiors.

Does Construct Type Matter? A Retrospective Review Comparing Outcomes of Distal Radius Fractures Treated with Standard Volar Plating versus Fragment-Specific Fixation.

Background Treatment of intra-articular distal radius fractures (DRFs) rests on anatomic internal fixation. Fragment-specific fixation (FSF) is applied when fracture pattern is too complex for standard volar plating (SVP), oftentimes with potential increased risk of complications. We hypothesized that patients undergoing FSF would achieve less wrist range of motion (ROM) with higher risk of complications compared with SVP. Methods We conducted a retrospective review of 159 consecutive patients undergoing DRF fixation from 2017 to 2020. Patients < 18 years old, < 8 weeks' follow-up, open fractures, ipsilateral trauma, and fractures requiring dorsal spanning plate were excluded. Patient demographics, specific construct type, AO fracture classification, ROM, and complications were assessed. ROM was calculated using average flexion, extension, supination, and pronation. t -Tests were used to determine differences in ROM among construct types. Results Ninety-two patients met all inclusion criteria: 59 underwent SVP and 33 underwent FSF. Average wrist ROM for patients undergoing SVP was 57 degrees/50 degrees flexion-extension and 87 degrees/88 degrees supination-pronation; average ROM for patients undergoing FSF was 55 degrees/49 degrees flexion-extension and 88 degrees/89 degrees supination-pronation. No significant differences were identified when comparing final wrist flexion ( p = 0.08), extension ( p = 0.33), supination ( p = 0.35), or pronation ( p = 0.21). Overall reoperation rate was 5% and higher for FSF (12%) versus SVP (2%). Highest reoperation rate was observed in the double volar hook cohort (80%; N = 4). Conclusion Construct type does not appear to affect final ROM if stable internal fixation is achieved. SVP and FSF had similar complication rates; however, double volar hook constructs resulted in increased reoperations likely from fixation failure and plate prominence. Level of Evidence Level IV, retrospective review.

Biomechanical Comparison of 5 Different Fixation Constructs in a Trapeziometacarpal Joint Arthrodesis Model

Trapeziometacarpal joint (TMC) arthrodesis has a high rate of nonunion. This biomechanical analysis sought to determine the stiffness of 5 fixation methods in a TMC joint arthrodesis model. Five fixation constructs were tested in a validated porcine model: crossed 1.1-mm K-wires, crossed 1.6-mm K-wires, crossed headless compression screws (HCSs), compression plating (CP), and locked compression plating (LCP). The cantilever bending stiffness was measured in abduction, adduction, flexion, and extension. Samples were loaded to failure in extension, and the mode of failure was examined. The crossed HCSs performed consistently well in all tests. Loading to failure resulted in screw pullout. In abduction and adduction, HCS and 1.6-mm K-wires were significantly stiffer than the other constructs. The mean load to failure in extension was similar in the HCS, CP, and LCP groups (304 N/mm, 311 N/mm, and 293 N/mm, respectively). There were no differences between CP and LCP in any biomechanical tests, and the mode of failure was through plate bending. The crossed 1.1-mm K-wires performed poorly in all tests. Crossed HCS displayed the greatest overall stability. Standard plating in compression mode and LCP had a similar biomechanical performance. The ideal construct stiffness required for the successful union after TMC joint arthrodesis is unknown, but HCS has the best overall biomechanical performance and, therefore, might be considered the best choice for this clinical setting.

Cultivation of previously uncultured sponge-associated bacteria using advanced cultivation techniques: A perspective on possible key mechanisms

Most of the microbes from natural habitats cannot be cultivated with standard cultivation in laboratory, and sponge-associated microbes are no exception. We used two advanced methods based on a continuous-flow bioreactor (CF) and in situ cultivation (I-tip) to isolate previously uncultivated marine sponge-associated bacteria. We also characterized the physiological properties of the isolates from each method and attempted to clarify the mechanisms operating in each cultivation method. A greater number of novel bacteria were isolated using CF and in situ cultivation compared to standard direct plating (SDP) cultivation. Most isolates from CF cultivation were poor growers (with lower specific growth rates and saturated cell densities than those of isolates from SDP cultivation), demonstrating that it is effective to carry out pre-enrichment cultivation targeting bacteria that are less competitive on conventional cultivation, especially K-strategists and bacterial types inhibited by their own growth. Isolates from in situ cultivation showed a positive influence on cell recovery stimulated by chemical compounds in the extract of sponge tissue, indicating that some of the bacteria require a “growth initiation factor” that is present in the natural environment. Each advanced cultivation method has its own distinct key mechanisms allowing cultivation of physiologically and phylogenetically different fastidious bacteria for cultivation compared with conventional methods.

(Digital Presentation) Operando Laser Scattering- and Inverted RDE-Based Approaches for the Development of Additive-Assisted Electrodeposited Co Interconnects

The development of Co interconnects by electrochemical means is more challenging than that of Cu-based analogues not only due to the ever decreasing critical feature dimensions but also to intrinsic complications of the water/Co system, as Co electrodeposition processes are inevitably accompanied by the competing hydrogen evolution reaction (HER). Aiming at enabling a more knowledge-driven Co interconnect development, we present herein two novel experimental approaches that reveal important insights on the complex interplay between additive-assisted Co electrodeposition and the HER.In a first instance, we present a custom-made inverted RDE instrument, particularly suitable for studying metal deposition processes that are accompanied by HER or any other gas evolving side reaction. We investigate the influence of a model redox-active suppressor additive on the electrochemical deposition of cobalt by means of linear sweep voltammetry and galvanostatic electrolysis coupled to online gas chromatography analysis. We find that under specific experimental conditions, addition of minor amounts of the additive to the standard Co-based virgin make-up solution significantly decreases the rate and efficiency of Co deposition, and favors instead the competing HER. Moreover, we identify and quantify the reductive conversion of the additive that accompanies the primary metal deposition process. Importantly, our approach complements standard screening Co plating studies as it succeeds to directly deconvolve the overall process into its three individual components, namely the metal ion reduction, the HER and the additive activation.Secondly, to develop understanding of proton dynamics in the diffusion layers generated by the metal electrodeposition processes we introduce a simple, non-invasive pH-sensing approach that is based on the Tyndall effect enhancement modulated by pH-controlled agglomeration events. We employ a laser beam laterally aligned to an electrode surface where additive-assisted cobalt deposition and hydrogen evolution take place simultaneously. This configuration allows the visualization of pH changes that result in precipitate formation and that extend to greater distances over patterned surfaces compared to flat ones, demonstrating a pH-guiding effect in superconformal metal deposition. The method provides real-time visualization of the pH dynamics with high lateral spatial resolution without physically or chemically influencing the investigated system. We suggest that applicability of the method can be extended to other processes where nanoaggregation/decomplexation inherently occur, as part of the investigated phenomena, at light-addressable interfaces.Overall, these investigations provide new insights for the further development of interconnect technology and metal deposition processes in general.. Figure 1

Identification and characterisation of a Novel SXT/R391 ICE mobile genetic element isolated from an Irish wastewater environment

Human and animal pathogenic bacteria are constantly being released into the environment through human activity. Many of these organisms can harbour genes such as virulence genes, antibiotic resistance and heavy metal resistance genes that are inserted into plasmids, transposons and Integrating Conjugating elements (ICEs), leading to potential spread. Such spread can be detected among water and soil communities and in particular in wastewater treatment plants. This makes wastewater and treatment plants a potential reservoir for mobile genetic elements including SXT/R391 ICEs, commonly detected amongst enterobacterial genera. Many plasmid and ICE genomes have been detected serendipitously from clinical sources but few have been identified without selection. Here we examined a domestic wastewater treatment plant to identify, isolate and characterize SXT/R391 ICE’s without selection. Standard microbial replica plating in conjunction with ICE specific (conserved integrase gene) PCR techniques were employed to identify an SXT/R391 ICE MGE using a range of enterobactial selective media. A Novel SXT/R391 ICE MGE was identified from a wastewater Proteus mirabilisstrain. Whole genome sequencing using Ilumina sequencing technology revealed a novel 81 kb element which on annotation contained 75 open reading frames. The “hotspot regions”, which contain adaptive genes, encoded a novel bacteriophage defence mechanisms but lacked other selectable determinants. With the continuous arms race between bacteria and phage, bacteria have developed novel resistance mechanism systems that protect the bacteria from phage. Such systems may be key adaptive mechanisms harboured by ICEs particularly in wastewater systems which will contain large phage populations.

Modified pin and plate fixation for low intercondylar fractures of the humerus: biomechanical study corroborated with a case series.

Establishing fracture union of low and comminuted intercondylar fractures of the humerus is inherently challenging. The purposes of the present study were to investigate the biomechanical effectiveness of pin & plate (PP) fixation compared to other dual-plating techniques by finite element analysis, and to present a technical description as well as retrospectively review the outcomes of PP fixation in such difficult fractures. Low-level intercondylar fracture 3D models of the humerus were virtually stabilized with three fixations on lateral side including PP, lateral pre-contoured locking compression plate (L-LCP), and variable angle lateral pre-contoured locking plate (VA-L-LCP) whereas medial pre-contoured locking compression plate (M-LCP) on medial side. Loading conditions under consideration were axial compression, internal rotation, posterior bending, and valgus rotation. Regarding the clinical series, eight patients with intra-articular and comminuted fractures of the distal humerus (6 intercondylar fractures, 1 fracture-subluxation, and 1 isolated lateral condylar fracture) were operated by isolated PP fixation or combinations of PP and the other standard implants. Data were collected on fracture union, perioperative complications, and objective clinical outcomes. Biomechanical results revealed the most instability of the fracture occurring under posterior bending. PP fixation presented comparable fracture stability and fragment displacement compared to other dual-plating fixations, except stress on the Kirschner wire under internal rotation which was higher than other fixations. Regarding the clinical series, fracture union was achieved in all cases with an average union time of 17weeks (range 12-20). All except one patient had good-to-excellent MEPS results with an average Disabilities of the Arm, Shoulder, and Hand (DASH) score of 14.6 (range 0-45) and an average arc of elbow motion of 107.5 degrees (range 60-140). By the biomechanical performance, PP fixation is a reliable technique for fixation of low intercondylar fractures of the humerus. Supported by the clinical outcomes, the present technique could be an alternative for this particular fracture especially when severe comminution prevents the use of the standard dual plating technique.