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Climate projection requires an accurate understanding for soil organic carbon (SOC) decomposition and its response to warming. An emergent view considers that environmental constraints rather than chemical structure alone control SOC turnover and its temperature sensitivity (i.e., Q10), but direct long‐term evidence is lacking. Here, using compound‐specific radiocarbon analysis of soil profiles along a 3300‐km grassland transect, we provide direct evidence for the rapid turnover of lignin‐derived phenols compared with slower‐cycling molecular components of SOC (i.e., long‐chain lipids and black carbon). Furthermore, in contrast to the slow‐cycling components whose turnover is strongly modulated by mineral association and exhibits low Q10, lignin turnover is mainly regulated by temperature and has a high Q10. Such contrasts resemble those between fast‐cycling (i.e., light) and mineral‐associated slow‐cycling fractions from globally distributed soils. Collectively, our results suggest that warming may greatly accelerate the decomposition of lignin, especially in soils with relatively weak mineral associations. [ABSTRACT FROM AUTHOR]

Microbial carbon use efficiency (CUE), a key parameter to characterize microbial carbon conversion efficiency, is assumed to be similar in soil models for different soil functional pools with varied organic matter composition and nutrient availability, that is, particulate organic matter (POM) and mineral‐associated organic matter (MAOM). However, empirical studies comparing microbial CUE in POM versus MAOM are largely lacking. It is not known whether microbial CUE variance may underpin the variant behaviour (i.e. turnover and composition) of different soil functional pools.Here we collected surface soils from 25 natural forests and grasslands with divergent edaphic properties, and compared microbial CUE in their POM versus MAOM using soil fractionation in combination with incubation using 18O‐labelled water. We also quantified edaphic properties, organic matter composition, microbial community structures and the stoichiometric imbalance of nitrogen (N) and phosphorus (P) relative to carbon based on the dissolved pool relative to microbial biomass (ImN and ImP) to investigate variables regulating microbial CUE and its variation in POM relative to MAOM (CUEPOM/CUEMAOM).In contrast to our expectation, microbial CUE did not consistently differ between POM and MAOM across sites, albeit with large inter‐sample variations in CUEPOM/CUEMAOM (from 0.3 to 4.4). Although MAOM had higher substrate quality, indicated by lower ratios of soil organic carbon to total nitrogen (C/NOM) and higher N‐compounds/aromatic ratios, and higher proportions of r‐strategists and fast‐growing bacteria in the microbial community than POM, POM and MAOM had similar degrees of N limitation (i.e. ImN), which was the best predictor of microbial CUE across all samples. Therefore, although MAOM harboured more N‐containing compounds than POM, N limitation was not necessarily lower, leading to an overall similar microbial CUE in POM and MAOM. Nevertheless, CUEPOM/CUEMAOM decreased with increasing P limitation in POM relative to MAOM.Overall, our paper presents a comprehensive, empirical study comparing microbial CUE in POM and MAOM of diverse soils, and our results support the use of similar microbial CUE for POM and MAOM in soil models, but also highlight potential contrasts in microbial CUE between soil pools under strong P limitation. Such inferences deserve attention under potentially increasing P limitation induced by N deposition. This study advances our mechanistic understanding of ecological patterns and processes from the organismic to the ecosystem scale based on soil microbial physiology and different soil functional pools. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Subsoil contains more than half of soil organic carbon (SOC) globally and is conventionally assumed to be relatively unresponsive to warming compared to the topsoil. Here, we show substantial changes in carbon allocation and dynamics of the subsoil but not topsoil in the Qinghai‐Tibetan alpine grasslands over 5 years of warming. Specifically, warming enhanced the accumulation of newly synthesized (14C‐enriched) carbon in the subsoil slow‐cycling pool (silt‐clay fraction) but promoted the decomposition of plant‐derived lignin in the fast‐cycling pool (macroaggregates). These changes mirrored an accumulation of lipids and sugars at the expense of lignin in the warmed bulk subsoil, likely associated with shortened soil freezing period and a deepening root system. As warming is accompanied by deepening roots in a wide range of ecosystems, root‐driven accrual of slow‐cycling pool may represent an important and overlooked mechanism for a potential long‐term carbon sink at depth. Moreover, given the contrasting sensitivity of SOC dynamics at varied depths, warming studies focusing only on surface soils may vastly misrepresent shifts in ecosystem carbon storage under climate change. [ABSTRACT FROM AUTHOR]

This case report describes a rare and interesting case of a patient with multiple myeloma complicated with light chain (LC) cast nephropathy and focal amyloidosis. The patient presented with acute kidney injury, anaemia and bone lesions. The diagnosis was confirmed by bone marrow biopsy, serum and urine electrophoresis and kidney biopsy. The patient was treated with isazomil, pomalidomide and dexamethasone combination chemotherapy, followed by autologous stem cell transplantation. The patient achieved clinical remission, stable renal function and improved serum lambda free LC levels. This case highlights the challenges and advances in the diagnosis and treatment of this condition. [ABSTRACT FROM AUTHOR]

Multivariate outcomes measured longitudinally over time are common in medicine, public health, psychology and sociology. The typical (saturated) longitudinal multivariate regression model has a separate set of regression coefficients for each outcome. However, multivariate outcomes are often quite similar and many outcomes can be expected to respond similarly to changes in covariate values. Given a set of outcomes likely to share common covariate effects, we propose the clustered outcome common predictor effect model and offer a two step iterative algorithm to fit the model using available software for univariate longitudinal data. Outcomes that share predictor effects need not be chosen a priori; we propose model selection tools to let the data select outcome clusters. We apply the proposed methods to psychometric data from adolescent children of HIV+ parents. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Mineral preservation and microbial residue production are vital for the accumulation of mineral‐associated organic carbon (MAOC) in soils. However, their relative importance and interactive effects remain unclear. Here MAOC content and composition are analyzed in tandem with soil mineral and microbial attributes along a weathering gradient on a volcanic soil sequence. We find that MAOC content increases with increasing mineral weathering states, accompanied by increasing microbial contribution to MAOC. Mineral attributes rather than microbial physiological traits are strongly related to MAOC contents, suggesting that weathering‐enhanced mineral preservation capacity overrides microbial residue production in governing MAOC accumulation by increasing reactive minerals. Furthermore, mineral attributes have a strong interactive effect with microbial traits on MAOC accumulation and composition, likely related to increasing fungal abundance in the microbial community with increasing weathering. These findings highlight that mineral weathering may effectively boost persistent SOC in synergy with microbial conversion in the long term. Plain Language Summary: The accrual of mineral‐associated organic carbon (MAOC) is one of the key mechanisms promoting the long‐term sequestration of atmospheric CO2 into soil organic carbon (SOC). Both microbial residue production and mineral preservation are vital for MAOC accumulation. However, their relative importance and interactive effects remain unclear, hampering our ability to understand how to effectively increase this important pool of persistent SOC. Here by analyzing MAOC content and composition in tandem with soil mineral and microbial attributes along a weathering gradient on a volcanic soil sequence (290 years–2.1 million years ago), we find that MAOC content increases with increasing weathering states, accompanied by increasing microbial contribution to MAOC. In contrast to short‐term studies where microbial residue production predominantly influences MAOC accumulation, weathering‐enhanced mineral preservation capacity overrides microbial residue production in governing MAOC accumulation in the long term by increasing reactive minerals. Furthermore, mineral attributes have a strong interactive effect with microbial traits on MAOC accumulation and composition, likely by enhancing the accumulation efficiency of microbial residues via affecting the microbial community composition. Our findings highlight mineral weathering may effectively boost persistent SOC pools in synergy with microbial conversion. Key Points: The relative importance of mineral versus microbial attributes and their interactive effects in MAOC accumulation was comparedWeathering‐enhanced mineral preservation overrode microbial residue production in governing MAOC accumulation over the weathering gradientMineral weathering strengthened microbial contribution to MAOC via affecting microbial community composition [ABSTRACT FROM AUTHOR]

Subsoils contain >50% of soil organic carbon (SOC) globally yet remain under‐investigated in terms of their response to climate changes. Recent evidence suggests that warmer, drier conditions in alpine grasslands induce divergent responses in SOC decomposition and carbon accrual in top‐ versus subsoils. However, longer term effects on microbial activity (i.e., catabolic respiration vs. anabolic growth) and belowground carbon cycling are not well understood. Here we utilized a field manipulation experiment on the Qinghai‐Tibetan Plateau and conducted a 110‐day soil incubation with and without 13C‐labeled grass litter to assess microbes' role as both SOC "decomposers" and "contributors" in the top‐ (0–10 cm) versus subsoils (30−40 cm) after 5 years of warming and drought treatments. Microbial mineralization of both SOC and added litter was examined in tandem with potential extracellular enzyme activities, while microbial biomass synthesis and necromass accumulation were analyzed using phospholipid fatty acids and amino sugars coupled with 13C analysis, respectively. We found that warming and, to a lesser extent, drought decreased the ratio of inorganic nitrogen (N) to water‐extractable organic carbon in the subsoil, intensifying N limitation at depth. Both SOC and litter mineralization were reduced in the subsoil, which may also be related to N limitation, as evidenced by lower hydrolase activity (especially leucine aminopeptidase) and reduced microbial efficiency (lower biomass synthesis and necromass accumulation relative to respiration). However, none of these effects were observed in the topsoil, suggesting that soil microbes became inactive and inefficient in subsoil but not topsoil environments. Given increasing belowground productivity in this alpine grassland under warming, both elevated root deposits and diminished microbial activity may contribute to new carbon accrual in the subsoil. However, the sustainability of plant growth and persistence of subsoil SOC pools deserve further investigation in the long term, given the aggravated N limitation at depth. [ABSTRACT FROM AUTHOR]

Objective: Genomic biomarkers predicting immune checkpoint inhibitor (ICI) treatment outcomes for Asian metastatic melanoma have been rarely reported. This study presents data on next‐generation sequencing (NGS) and tumour microenvironment biomarkers in 33 cases. Methods: Thirty‐three patients with advanced melanoma, who underwent ICI treatment at the Chang Gung Memorial Hospital in Taiwan, were recruited. The study evaluated clinical outcomes, including response rate, disease control rate, progression‐free survival (PFS) rate and overall survival (OS) rate. Archived tissue samples from 33 cases were subjected to NGS by ACTOnco, and ACTTME was employed in 25 cases. Results: The most prevalent driver mutations were BRAF mutations (24.2%), followed by NRAS (15.2%), KIT (12.1%), KRAS (9.1%) and NF1 (9.1%) mutations. Acral/mucosal melanomas exhibited distinct mutation patterns compared to non‐acral melanomas. Tumour mutational burden estimated using ACTOnco was not associated with ICI efficacy. Notably, genetic alterations in the p53 pathway (CDKNA2 loss, MDM2 gain/amplification and TP53 mutation) accounted for 36.4% and were significantly associated with unfavourable PFS (median PFS 2.7 months vs. 3.9 months, P = 0.0394). Moreover, 26 genes were identified as differentially expressed genes that were upregulated in patients with clinical benefits compared to those without benefits. Four genes, GZMH, GZMK, AIM2 and CTLA4, were found to be associated with both PFS and OS. Conclusion: Genetic alterations in the p53 pathway may be critical in Asian patients with melanoma undergoing ICI treatment. Further investigation is required to explore this mechanism and validate these findings. [ABSTRACT FROM AUTHOR]

Forest ecosystems are important global soil carbon (C) reservoirs, but their capacity to sequester C is susceptible to climate change factors that alter the quantity and quality of C inputs. To better understand forest soil C responses to altered C inputs, we integrated three molecular composition published data sets of soil organic matter (SOM) and soil microbial communities for mineral soils after 20 years of detrital input and removal treatments in two deciduous forests: Bousson Forest (BF), Harvard Forest (HF), and a coniferous forest: H.J. Andrews Forest (HJA). Soil C turnover times were estimated from radiocarbon measurements and compared with the molecular‐level data (based on nuclear magnetic resonance and specific analysis of plant‐ and microbial‐derived compounds) to better understand how ecosystem properties control soil C biogeochemistry and dynamics. Doubled aboveground litter additions did not increase soil C for any of the forests studied likely due to long‐term soil priming. The degree of SOM decomposition was higher for bacteria‐dominated sites with higher nitrogen (N) availability while lower for the N‐poor coniferous forest. Litter exclusions significantly decreased soil C, increased SOM decomposition state, and led to the adaptation of the microbial communities to changes in available substrates. Finally, although aboveground litter determined soil C dynamics and its molecular composition in the coniferous forest (HJA), belowground litter appeared to be more influential in broadleaf deciduous forests (BH and HF). This synthesis demonstrates that inherent ecosystem properties regulate how soil C dynamics change with litter manipulations at the molecular‐level. Across the forests studied, 20 years of litter additions did not enhance soil C content, whereas litter reductions negatively impacted soil C concentrations. These results indicate that soil C biogeochemistry at these temperate forests is highly sensitive to changes in litter deposition, which are a product of environmental change drivers. [ABSTRACT FROM AUTHOR]

Solar steam generation is a promising strategy for harvesting solar energy for diverse applications such as desalination and wastewater treatment. Here, we demonstrate the fabrication of polypyrrole modified sugarcane (PPy‐SC) as efficient photothermal material for solar steam generation. The PPy‐SC possesses various close‐packed open channels in horizontal plane and super hydrophilic wettability which is beneficial for rapid transportation of water molecules. In combination with its abundant porosity (47%), low apparent density (80 mg cm−3), low thermal conductivity (0.042 W m−1 K−1), and broad light absorption (90%). The prepared PPy‐SC exhibits a high evaporation rate of 1.59 kg m−2 h−1 and conversion efficiency of 90.6%, under 1 sun irradiation. In addition, the PPy‐SC also shows good performance in desalination. With the merits of low‐cost, eco‐friendly, simple fabrication process, high solar energy conversion efficiency, the PPy‐SC shows great potential as an efficient photothermal material for solar steam generation. [ABSTRACT FROM AUTHOR]

Aims The BRAF V600 mutation has been shown to be clinically meaningful in terms of both the prognosis and sensitivity of BRAF inhibitors in patients with metastatic melanoma. Recently, a BRAF V600E mutation-specific antibody, VE1, was generated for the detection of tumors bearing BRAF V600E mutations. To determine the clinical value of immunohistochemical testing, we compared the prevalence of mutant BRAF detected by VE1 with direct sequencing results. Methods Paraffin-embedded, formalin-fixed melanoma biopsies were analyzed for the BRAF mutation status by immunohistochemistry with the VE1 antibody. Sanger sequencing was applied to verify the immunohistochemical results. Results A total of 73 melanoma cases with tumor samples from primary lymph nodes and metastatic sites were selected for this study. Direct sequencing demonstrated that 18 of 73 cases (24.6%) harbored the BRAF V600 mutation: 17 with V600E and one with V600K. All 18 tumors shown to harbor the BRAF V600E/K mutations were VE1-positive. One additional case was false-positive for VE1. The sensitivity and specificity of VE1 was 100% (18/18) and 98% (54/55), respectively. The overall concordance between the immunohistochemical method and direct sequencing was excellent (98.6%). Conclusions Our findings demonstrate that immunohistochemical analysis using VE1 constitutes a highly sensitive test for the detection of BRAF mutations and suggest that this cost-effective method is suitable as a rapid diagnostic approach complementary to molecular testing. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the mutation rates of Kirsten ras oncogene homolog gene (KRAS) among patients with nonsmall cell lung cancer (NSCLC). It mentions that the researchers performed mutation analysis of KRAS and correlated its results with clinicopathological features. It affirms that the authors concluded that the KRAS mutation rate is too low in terms of being considered as an important factor in resisting tyrosine kinase inhibitor (TKI).