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Studies on self-binding hot-pressed fiberboards using agricultural byproducts aim to identify alternatives to scarce wood resources. Particle size and mixture significantly impact strength, although direct comparisons are difficult due to differences in study methods. We evaluated fiberboards made from the two perennial biomass crops Miscanthus and Paulownia and compared them to Picea (spruce), using five distinct particle size blends prepared from milled and sieved particles, respectively. The boards were evaluated for their modulus of elasticity, modulus of rupture, reaction to fire, water absorption, and thickness swelling. All specimens exhibited normal ignitability, as defined by Euroclass E according to EN13501-1. The results indicate that mechanical performance improves with increasing density, which correlates with higher proportions of finer particles. Notably, the finer Miscanthus blends and all Paulownia samples met the modulus of elasticity requirements of EN 622. [ABSTRACT FROM AUTHOR]

The rapid tooling of mold inserts for injection molding allows for very fast product development, as well as a highly customized design. For this, a combination of rapid prototyping methods with suitable polymer materials, like the high-performance thermoplastic polymer polyetheretherketone (PEEK), should be applied. As a drawback, a huge processing temperature beyond 400 °C is necessary for material extrusion (MEX)-based 3D printing; here, Fused Filament Fabrication (FFF) requires a more sophisticated printing parameter investigation. In this work, suitable MEX printing strategies, covering printing parameters like printing temperature and speed, for the realization of two different mold insert surface geometries were evaluated, and the resulting print quality was inspected. As a proof of concept, ceramic injection molding was used for replication. Under consideration of the two different test structures, the ceramic feedstock could be replicated successfully and to an acceptable quality without significant mold insert deterioration. [ABSTRACT FROM AUTHOR]

Simple Summary: In soft tissue sarcomas, unplanned resections, so-called Whoops procedures, do occur frequently. Whether re-resection reduces local recurrence or improves overall survival is unclear. 185 patients who underwent unplanned resection were included. Group A (n = 156) underwent re-excision, while Group B (n = 29) not. Residual tumor was observed in 60% of the resected tumors. In Group A, 8% of the patients developed local recurrence, in Group B 14% (n.s.). Overall survival and local recurrence-free survival were not different between the groups. However, within the subgroup of patients with residual disease in the re-resected specimen, survival was compromised, and the local recurrence rate was higher. Particularly for low-grade lesions, more patients could be treated without re-resections. Background: In soft tissue sarcomas, unplanned resections, or so-called Whoops procedures, do occur quite frequently, thus primarily owing to the abundant presence of benign lesions. Whether re-resection reduces local recurrence or improves overall survival remains a topic of ongoing debate. The principle objective of this study was to analyze the outcomes of patients with soft tissue sarcomas of the extremities or trunk wall after an incidental marginal resection by comparing re-resections to individuals who declined the procedure. Methods: A total of 185 patients who underwent unplanned resection were included. These patients were stratified into two groups: Group A (n = 156) underwent re-excision, while Group B (n = 29) was treated conservatively. Depending on the clinical scenario, radio- or chemotherapy was either administered in a neoadjuvant or an adjuvant setting. The presence of residual tumor and metastatic disease was documented. Clinical outcomes, specifically local recurrence (LR), local recurrence-free survival (LRFS) and overall survival (OS), were utilized for evaluation. Results: Group B exhibited significantly larger tumors (p < 0.0001) and a higher mean age than Group A. Among the patients in Group A, 11 (5.9%) had contaminated resection margins (R1), and residual disease (RD) was observed in 93 (59.6%) of the resected specimens. In group B, 10 patients received adjuvant radiotherapy alone, 5 received chemotherapy alone, and 13 underwent a combined approach consisting of both radio- and chemotherapy. In Group A, 8% (n = 12) of the patients developed local recurrence (LR) during the observation period. Conversely, in Group B, this amount was 14% (n = 4) (n.s.). Of the 12 LR in Group A, 10 were found in the subgroup with residual disease. Overall survival and local recurrence-free survival were not significantly different between the groups. A total of 15% (n = 24) of the patients in Group A developed metastatic disease, while 10% (n = 3) in Group B developed metastatic disease (n.s.). Conclusions: Following the reresection of unplanned resected STS, there was no statistically significant difference observed in overall survival or LR compared to patients who did not undergo re-resection. However, within the subgroup of patients with residual disease in the re-resected specimen, the OS was compromised, and the LR rate was higher. Particularly for low-grade lesions, adopting a more conservative approach seems to be justified. [ABSTRACT FROM AUTHOR]

Simple Summary: In a cohort of 828 patients undergoing surgery for sarcomas of the extremities, pelvis, and trunk, approximately half of them were advised to receive radiotherapy. Notably, 4.7% declined the recommended treatment regimen, resulting in a decrease of both overall survival and local recurrence-free survival. Similarly, 40% of patients within the same group were advised to undergo chemotherapy; 8.8% of these patients rejected the recommendation, leading to a reduced local recurrence-free survival. Enhancing physician-patient communication and addressing underutilization of recommended therapies in sarcoma patients should be a priority for surgeons and oncologists alike. Background: In soft tissue or bone sarcomas, multimodal therapeutic concepts represent the standard of care. Some patients reject the therapeutic recommendations due to several reasons. The aim of this study was to assess the impact of that rejection on both prognosis and local recurrence. Methods: Between 2012 and 2019, a total of 828 sarcoma patients were surgically treated. Chemotherapy was scheduled as a neoadjuvant, and adjuvant multi-agent therapy was performed following recommendations from an interdisciplinary tumor board. Radiotherapy, if deemed appropriate, was administered either in a neoadjuvant or an adjuvant manner. The recommended type of therapy, patient compliance, and the reasons for refusal were documented. Follow-ups included local recurrences, diagnosis of metastatic disease, and patient mortality. Results: Radiotherapy was recommended in 407 (49%) patients. A total of 40 (10%) individuals did not receive radiation. A reduction in overall survival and local recurrence-free survival was evident in those patients who declined radiotherapy. Chemotherapy was advised for 334 (40%) patients, 250 (75%) of whom did receive all recommended cycles. A total of 25 (7%) individuals did receive a partial course while 59 (18%) did not receive any recommended chemotherapy. Overall survival and local recurrence-free survival were reduced in patients refusing chemotherapy. Overall survival was worst for the group of patients who received no chemotherapy due to medical reasons. Refusing chemotherapy for non-medical reasons was seen in 8.8% of patients, and refusal of radiotherapy for non-medical reasons was seen in 4.7% of patients. Conclusions: Divergence from the advised treatment modalities significantly impacted overall survival and local recurrence-free survival across both treatment modalities. There is an imperative need for enhanced physician-patient communication. Reducing treatment times, as achieved with hypofractionated radiotherapy and with therapy in a high-volume sarcoma center, might also have a positive effect on complying with the treatment recommendations. [ABSTRACT FROM AUTHOR]

In subtractive manufacturing processes, swarf, burrs or other residues are produced, which can impair the function of a tribological system (e.g., journal bearings). To prevent premature engine damage, cleanliness requirements are defined for production processes. Damaging particle tests are an experimental approach for validating these defined cleanliness requirements. This methodical approach is not yet widely used. For one, the test setup must be developed and proven for the respective application. For another, in order to carry out the tests in a systematic manner, defined test particles with properties similar to those of the contaminants encountered in reality are required. In the second part of the paper, the process chain for manufacturing artificial test swarf by micro powder injection molding (MicroPIM) is described. The size and shape of the swarf were derived from real swarf via several abstraction processes. Although certain design guidelines for MicroPIM parts could not be taken into account, the targeted manufacturing tolerances were achieved in most cases. During demolding, it became apparent that the higher ejection forces of the free-formed geometries must be taken more into account in the design of the mold. The experiments on the test setup also revealed that the artificial test swarf was unexpectedly brittle and was therefore ground up in the bearing gap without causing any substantial damage to the bearing. Thus, the artificial test swarf in its current sintered state is not a suitable substitute for micromilled swarf. However, MicroPIM could still be used to manufacture test particles in applications involving lower mechanical forces. [ABSTRACT FROM AUTHOR]

High-performance thermoplastics like polyetheretherketone (PEEK), with their outstanding thermal stability, mechanical properties and chemical stability, have great potential for various structural applications. Combining with additive manufacturing methods extends further PEEK usage, e.g., as a mold insert material in polymer melt processing like injection molding. Mold inserts must possess a certain mechanical stability, a low surface roughness as well as a good thermal conductivity for the temperature control during the molding process. With this in mind, the commercially available high-performance thermoplastic PEEK was doped with small amounts of carbon nanotubes (CNT, 6 wt%) and copper particles (10 wt%) targeting enhanced thermomechanical properties and a higher thermal conductivity. The composites were realized by a commercial combined compounder and filament maker for the usage in a material extrusion (MEX)-based 3D-printer following the fused filament fabrication (FFF) principle. Commercial filaments made from PEEK and carbon fiber reinforced PEEK were used as reference systems. The impact of the filler and the MEX printing conditions like printing temperature, printing speed and infill orientation on the PEEK properties were characterized comprehensively by tensile testing, fracture imaging and surface roughness measurements. In addition, the thermal conductivity was determined by the laser-flash method in combination with differential scanning calorimetry and Archimedes density measurement. The addition of fillers did not alter the measured tensile strength in comparison to pure PEEK significantly. The fracture images showed a good printing quality without the MEX-typical voids between and within the deposited layers. Higher printing temperatures caused a reduction of the surface roughness and, in some cases, an enhanced ductile behavior. The thermal conductivity could be increased by the addition of the CNTs. Following the given results, the most critical process step is the compounding procedure, because for a reliable process–parameter–property relationship, a homogeneous particle distribution in the polymer matrix yielding a reliable filament quality is essential. [ABSTRACT FROM AUTHOR]

Simple Summary: T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) acts as an immune checkpoint on exhausted T cells and has been associated with dismal outcomes in various solid tumors. TIM3 is currently being evaluated as an immunotherapeutic target in multiple clinical trials. Our study shows the significant tumor cell expression of TIM-3 in specific subsets of patients with high risk soft tissue sarcomas (HR-STS). We demonstrate an interaction between TIM-3, tumor infiltrating lymphocyte (TIL) counts and PD-1/PD-L1 expression in patients with HR-STS. TIM-3 could qualify as a potential immunotherapeutic target in HR-STS. (1) Background: The expression of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), an immune checkpoint receptor on T cells, has been associated with dismal outcomes and advanced tumor stages in various solid tumors. The blockade of TIM-3 is currently under examination in several clinical trials. This study examines TIM-3 expression in high-risk soft tissue sarcomas (HR-STS). (2) Methods: Tumor cell expression of TIM-3 on protein level was analyzed in pre-treatment biopsies of patients with HR-STS. TIM-3 expression was correlated with clinicopathological parameters including tumor-infiltrating lymphocyte (TIL) counts, programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PDL-1) expression in patients with HR-STS. Survival dependent on the expression of TIM-3 was analyzed. (3) Results: TIM-3 expression was observed in 101 (56%) out of 179 pre-treatment biopsies of patients with HR-STS. TIM-3 expression was significantly more often observed in undifferentiated pleomorphic sarcomas (UPS) compared to other histological subtypes (p < 0.001), high TIL counts (p < 0.001), and high PD-1 (p < 0.001) and PD-L1 expression (p < 0.001). TIM-3 expression did not have a prognostic impact on survival in patients with HR-STS. (4) Conclusions: This is the first study to demonstrate a significant tumor cell expression of TIM-3 in specific subsets of patients with HR-STS. TIM-3 qualifies as a potential immunotherapeutic target in HR-STS. [ABSTRACT FROM AUTHOR]

We present a tunable diode laser spectrometer with a novel, rapid time multiplexed direct absorption- and wavelength modulation-spectroscopy operation mode. The new technique allows enhancing the precision and dynamic range of a tunable diode laser absorption spectrometer without sacrificing accuracy. The spectroscopic technique combines the benefits of absolute concentration measurements using calibration-free direct tunable diode laser absorption spectroscopy (dTDLAS) with the enhanced noise rejection of wavelength modulation spectroscopy (WMS). In this work we demonstrate for the first time a 125 Hz time division multiplexed (TDM-dTDLAS-WMS) spectroscopic scheme by alternating the modulation of a DFB-laser between a triangle-ramp (dTDLAS) and an additional 20 kHz sinusoidal modulation (WMS). The absolute concentration measurement via the dTDLAS-technique allows one to simultaneously calibrate the normalized 2f/1f-signal of the WMS-technique. A dTDLAS/WMS-spectrometer at 1.37 µm for H2O detection was built for experimental validation of the multiplexing scheme over a concentration range from 50 to 3000 ppmV (0.1 MPa, 293 K). A precision of 190 ppbV was achieved with an absorption length of 12.7 cm and an averaging time of two seconds. Our results show a five-fold improvement in precision over the entire concentration range and a significantly decreased averaging time of the spectrometer. [ABSTRACT FROM AUTHOR]

Simple Summary: Sarcomas are malignant tumors of soft tissues or bone. While limb salvage surgery (LSS) is the standard treatment, amputation is an option especially in local recurrence (LR) or complications after LSS. Two groups with primary amputations (n = 120) or secondary amputations after failed LSS due to LR or complications (n = 29) were compared. Five-year LR-free survival was 84% and 17 (16%) patients developed LR, of which 16 were in group I and only one in group II. Overall survival (OS) at five years was 44%, and the rate was identical in both groups. In those group II patients who had a secondary amputation after LSS due to contaminated margins or LR (n = 12) five-year OS was 33% compared to 48% in patients with complications (n = 17). This study indicates the worse oncological outcomes with respect to OS of sarcoma patients needing an amputation as compared to LSS. Patients with primary amputation or those who had a secondary amputation after failed LSS for whatever reason showed the same results. Background: Sarcomas are rare, malignant tumors of soft tissues or bone. Limb salvage surgery (LSS) is the standard treatment, but amputation is still an option, especially in local recurrence or complications after LSS. Methods: We retrospectively reviewed indications and oncological outcomes in patients who underwent an amputation. Two groups with either primary amputations (n = 120) or with secondary amputations after failed LSS with local recurrence or complications (n = 29) were compared with the main end points of LRFS and OS. Results: Five-year LRFS was 84% with 17 (16%) patients developing local recurrence, of which 16 (13%) occurred in group I. Forty-two (28%) patients developed metastatic disease and overall survival at five years was 44%. Overall survival (OS) was the same in both groups. In those group II patients who had a secondary amputation due to LR or insufficient margins after LSS (n = 12) the five-year OS was 33% compared to 48% in patients with amputation due to complications (n = 17) (n.s.). Conclusions: This study indicates the worse oncological outcomes with respect to OS of sarcoma patients requiring an amputation as compared to LSS. Patients with primary amputation or those who had a secondary amputation after failed LSS for whatever reason showed the same oncological results. [ABSTRACT FROM AUTHOR]

Simple Summary: High-risk soft tissue sarcomas (HR-STS) account for less than 1% of all malignancies in adults. Despite optimal local treatment, almost half of patients will die within five years of their diagnosis. Chemoresistance is a major responsible mechanism for treatment failure in advanced tumor stages. In contrast to other cancer types, molecular predictors of response to chemotherapy and survival have not been identified and put into clinical practice by now. We analyzed the predictive value of two molecules involved in the working and resistance mechanisms to doxorubicin, TOP2A and SIRT1, in a large cohort of locally advanced HR-STS who underwent a neoadjuvant anthracycline-based chemotherapy with a long-term follow-up. Our results show sarcoma subtype-specific patterns of TOP2A and SIRT1 expression. We demonstrate significant differences in overall survival according to the TOP2A and SIRT1 expression status. Both markers can be used as clinically significant predictive indicators for HR-STS patients scheduled for neoadjuvant anthracycline-based chemotherapy. Molecular predictors of response to chemotherapy and survival have not been put into clinical practice in high-risk soft tissue sarcomas (HR-STS) by now. The expression of TOP2A and SIRT1 has implications for the mechanism of action of doxorubicin, which is the backbone of chemotherapy in HR-STS. Pre-treatment samples of 167 patients with HR-STS were collected. Protein expression levels of TOP2A and SIRT1 were evaluated with tissue microarrays and immunohistochemistry and correlated with clinicopathological parameters, including overall survival (OS). The expression of TOP2A and SIRT1 was seen in 47% and 60% of patients with HR-STS, respectively. TOP2A expression was associated with higher tumor grading and shorter 5-year OS. The expression of SIRT1 was correlated with a better 5- and 10-year OS. The combination of high SIRT1 and low TOP2A ("Top survivors") significantly predicted a better OS compared to other biomarker combinations. A multivariate analysis confirmed the expression of SIRT1 and the "Top survivor" biomarker combination as independent predictive factors of OS. This is the first study to associate SIRT1 overexpression with a statistically significant prolongation of OS in HR-STS. Both individual markers and their combination can be used as predictive indicators for HR-STS patients scheduled for neoadjuvant anthracycline-based chemotherapy. [ABSTRACT FROM AUTHOR]

Simple Summary: A precise diagnosis is key in the correct treatment of sarcomas. However, which kind of biopsy should be done: A minimal invasive core needle biopsy (CNB) or an incisional biopsy (IB), yielding more tissue but requiring surgery? We compared the results of both methods after resection of musculoskeletal sarcomas in respect to the accuracy of the diagnosis. In total, 417 patients with 472 biopsies and final sarcoma diagnoses were included. The rate of unequivocal sarcoma diagnoses was 84.9% with CNB vs. 87.6% with IB (p = 0.465). The rate of repeat biopsies was higher with CNB as compared to IB (p = 0.003). There was no difference in the determination of the sarcoma subtype or the grade of malignancy. Sarcoma subtype, bone vs. soft tissue, and the biopsy technique utilized did not influence the sensitivity. The single exception to this was with chondrosarcomas, where IB was significantly superior to CNB (p = 0.024). Based on our data, the minimal invasive technique can be used without disadvantages in the majority of patients. Background: There is no evidence as to the diagnostic value of the two most frequently used methods of biopsies in sarcomas: Incisional or core needle biopsy. The aim of our study was to evaluate the diagnostic sensitivity of the incisional and the core needle biopsy techniques in the diagnosis of bone and soft tissue sarcomas. Methods: We included 417 patients with a definitive diagnosis of bone or soft tissue sarcoma in whom a total of 472 biopsies had been performed. We correlated the results of the biopsies with the result of the definitive histopathological examination of the resected tumor. Dignity, entity, and grading (whenever possible) of the tissue samples were evaluated. Results: A total of 258 biopsies (55%) were performed in order to diagnose a soft tissue tumor and 351 biopsies (74.4%) were core needle biopsies. The number of repeat core needle biopsies, necessitated because of inconclusive histopathological results, was significantly higher (50 vs. 5; p = 0.003). We observed no significant difference regarding dignity, entity, and grading between the 2 different types of biopsies. Only with regards to the determination of dignity and entity of chondroid tumors, incisional biopsy was superior with statistical significance (p = 0.024). Conclusions: This study represents the largest study on biopsies for bone and soft tissue sarcomas. Based only on our results, we are unable to favor one method of biopsy and found high accuracy with both methods. Considering the potential complications, the added oncological risks of incisional biopsies and the ready availability of core needle biopsies, the latter, in our assessment, represents a valid and favourable method for bone and soft tissue sarcomas. [ABSTRACT FROM AUTHOR]

Simple Summary: In soft tissue sarcomas the width of surgical margins after resection determines the extent of surgery and the function after resection. But how far is really necessary? 305 patients with deep-seated, G2/3 soft tissue sarcomas of the extremity, the trunk wall, or the pelvis were reviewed. The 5-year local recurrence-free survival (LRFS) was 82%. Overall survival (OS) at 5 years was 66%. Positive (contaminated) margins worsened LRFS and OS. A margin of >10 mm did not improve LRFS and OS as compared to one of >5 mm. A resection margin of <1 mm showed a trend but not significantly better LRFS or OS compared to a contaminated margin. In conclusion the margin should at least be free of tumor, in sound tissue. A margin of >5 mm sound tissue seems to be sufficient. Resecting more tissue does not benefit the patient. Background: The significance of surgical margins after resection of soft tissue sarcomas in respect to local-recurrence-free survival and overall survival is evaluated. Methods: A total of 305 patients with deep-seated, G2/3 soft tissue sarcomas (STS) of the extremity, the trunk wall, or the pelvis were reviewed. The margin was defined according to the Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) classification system (R0-2), the Union Internationale Contre le Cancer (UICC) classification (R + 1 mm) for which a margin <1 mm is included into the R1 group, and in groups of <1 mm, 1–5 mm, >5 mm, or >10 mm. Results: Of these patients, 31 (10.2%) had a contaminated margin, 64 (21%) a margin of <1 mm, 123 (40.3%) a margin of 1–5 mm, 47 (15.4%) a margin of >5 mm, and 40 (13.1%) a margin of >10 mm. The 5-year local recurrence-free survival (LRFS) was 81.6%. Overall survival (OS) at 5 years was 65.9%. Positive margins worsened LRFS and OS. A margin of >10 mm did not improve LRFS and OS as compared to one of >5 mm. Conclusions: A resection margin of <1 mm showed a trend but not significantly better LRFS or OS compared to a contaminated margin. This finding supports use of the UICC classification. A margin of more than 10 mm did not improve LRFS or OS. [ABSTRACT FROM AUTHOR]

This study discusses the influence of soil compaction on runoff generation with a special focus on forested Andosol sites. Because of their typical soil physical characteristics (low bulk density, high pore volumes) and the existent land use, these areas are expected to show low to no measurable overland flow during heavy rainfall events. However, due to heavy machinery traffic in the course of forestry actions and pumice excavations, skid trails have been established. Here, a distinct shift of soil dry bulk density (DBD) was observable, using a detailed soil mapping and data interpolation in order to generate in-depth DBD-cross profiles. Additionally, infiltration measurements and rainfall simulations (I = 45 mm·h−1, t = 30 min) were conducted to evaluate effects of observed soil compaction on infiltration rates and overland flow formation. Results show that soil compaction was increased by 21% on average in skid trail wheel ruts. As a consequence, observed runoff was 8.5-times higher on skid trails, while saturated hydraulic conductivity was diminished by 36%. These findings show, that soil compaction leads to a higher possibility of runoff formation during heavy rainfall events, especially at sites which showed initial conditions with presumably low tendencies of runoff formation. [ABSTRACT FROM AUTHOR]