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1.
The mycoflora, moisture content and aflatoxin contamination of pigeon pea (Cajanus cajan (L.) Millisp) stored in jute sacks and iron bins were determined at monthly intervals for a year. The predominant fungi on freshly harvested seeds wereAlternaria spp.,Botryodiplodia theobromae, Fusarium spp. andPhoma spp. These fungi gradually disappeared from stored seeds with time and by 5–6 months, most were not isolated. The fungi that succeeded the initially dominant ones were mainly members of the generaAspergillus, Penicillium andRhizopus. Population of these fungi increased up to the end of one year storage. Higher incidence of mycoflora andAspergillus flavus were recorded in jute-sack samples throughout the storage period. The moisture content of stored seeds was found to fluctuate with the prevailing weather condition, being low during the dry season and slightly high during the wet season. The stored seeds were free of aflatoxins for 3 and 5 months in jute sacks and iron bins respectively. The level of aflatoxins detected in jute-sack storage system was considerably higher than that occurring in the iron bin system. Of 196 isolates ofA. flavus screened, 48% were toxigenic in liquid culture (54% from jute sacks and 41% from iron bins).  相似文献   
2.
Compared to conjugated polymers, small‐molecule organic semiconductors present negligible batch‐to‐batch variations, but presently provide comparatively low power conversion efficiencies (PCEs) in small‐molecular organic solar cells (SM‐OSCs), mainly due to suboptimal nanomorphology. Achieving precise control of the nanomorphology remains challenging. Here, two new small‐molecular donors H13 and H14 , created by fluorine and chlorine substitution of the original donor molecule H11 , are presented that exhibit a similar or higher degree of crystallinity/aggregation and improved open‐circuit voltage with IDIC‐4F as acceptor. Due to kinetic and thermodynamic reasons, H13 ‐based blend films possess relatively unfavorable molecular packing and morphology. In contrast, annealed H14 ‐based blends exhibit favorable characteristics, i.e., the highest degree of aggregation with the smallest paracrystalline π–π distortions and a nanomorphology with relatively pure domains, all of which enable generating and collecting charges more efficiently. As a result, blends with H13 give a similar PCE (10.3%) as those made with H11 (10.4%), while annealed H14 ‐based SM‐OSCs have a significantly higher PCE (12.1%). Presently this represents the highest efficiency for SM‐OSCs using IDIC‐4F as acceptor. The results demonstrate that precise control of phase separation can be achieved by fine‐tuning the molecular structure and film formation conditions, improving PCE and providing guidance for morphology design.  相似文献   
3.
Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor π? π interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs.  相似文献   
4.
Abstract

In Nigeria, most strains of Ralstonia solanacearum, the causative agent of tomato bacterial wilt disease; belong to race 1 biovar III (RIB3). Control strategies to assuage its destructive effect are highly necessary. A randomised complete-block design (RCBD) was used for the experiment. Thymol (0.7%) and Acibenzolar-s-methyl (ASM, 30 and 15?µg/ml) were used. Results indicated that the combination of thymol and ASM recorded the highest numbers of days for fruiting in Beske which were 74 and 75 while 59 and 60?days were recorded for UC82-B in both early and late seasons, respectively. When thymol and/or ASM were applied, bacterial wilt disease incidence and disease severity were significantly reduced and this was translated to a significant yield increase when compared with the untreated control plots. The results suggested that the combined application of thymol and ASM could be advantageous to tomato-growing farmers where R. solanacearum is prevalent.  相似文献   
5.
Open‐circuit voltage (VOC) losses in organic photovoltaics (OPVs) inhibit devices from reaching VOC values comparable to the bandgap of the donor–acceptor blend. Specifically, nonradiative recombination losses (?Vnr) are much greater in OPVs than in silicon or perovskite solar cells, yet the origins of this are not fully understood. To understand what makes a system have high or low loss, an investigation of the nonradiative recombination losses in a total of nine blend systems is carried out. An apparent relationship is observed between the relative domain purity of six blends and the degree of nonradiative recombination loss, where films exhibiting relatively less pure domains show lower ?Vnr than films with higher domain purity. Additionally, it is shown that when paired with a fullerene acceptor, polymer donors which have bulky backbone units to inhibit close π–π stacking exhibit lower nonradiative recombination losses than in blends where the polymer can pack more closely. This work reports a strategy that ensures ?Vnr can be measured accurately and reports key observations on the relationship between ?Vnr and properties of the donor/acceptor interface.  相似文献   
6.
7.

Introduction

Metastatic disease in the sinonasal region occurs rarely and the primary site may be elusive. This case highlights the possibility of an occult renal tumor manifesting with nasal symptoms and the risk of severe bleeding following nasal biopsy.

Case presentation

We report the case of a 79-year-old Caucasian woman who presented with a six-week history of intermittent left-sided nosebleeds. She was fit, without previous surgery or anticoagulation. Nasal endoscopy and computed tomography showed a hemorrhagic mass occupying her left ethmoid cells and middle meatus. After a highly hemorrhagic biopsy, the lesion was histologically confirmed as clear cell carcinoma. Screening revealed a right kidney mass with widespread metastases. Palliative radiotherapy to the sinonasal metastasis and systemic treatment rendered her free of symptoms nine months after initial presentation.

Conclusions

General practitioners and ear, nose and throat (ENT) doctors are very often confronted with epistaxis. A small minority of patients with epistaxis show a primary or metastatic nasal mass. Detection of the origin of secondary sinonasal masses requires a high index of suspicion and examination of infraclavicular sites by a multidisciplinary team. Renal cell carcinoma metastases are prone to severe bleeding during any surgical intervention, therefore, preoperative embolization is recommended. Resection or radiotherapy to the sinonasal metastasis of renal origin is justified in order to prevent recurrent nosebleeds.
  相似文献   
8.
We have identified an Arabidopsis mutant that displays enhanced disease resistance (edr2) to the biotrophic powdery mildew pathogen Erysiphe cichoracearum. Inhibition of fungal growth on edr2 mutant leaves occurred at a late stage of the infection process and coincided with formation of necrotic lesions approximately 5 days after inoculation. Double-mutant analysis revealed that edr2-mediated resistance is suppressed by mutations that inhibit salicylic acid (SA)-induced defense signaling, including npr1, pad4 and sid2, demonstrating that edr2-mediated disease resistance is dependent on SA. However, edr2 showed normal responses to the bacterial pathogen Pseudomonas syringae pv. tomato strain DC3000. EDR2 appears to be constitutively transcribed in all tissues and organs and encodes a novel protein, consisting of a putative pleckstrin homology (PH) domain and a steroidogenic acute regulatory protein-related lipid-transfer (START) domain, and contains an N-terminal mitochondrial targeting sequence. The PH and START domains are implicated in lipid binding, suggesting that EDR2 may provide a link between lipid signaling and activation of programmed cell death mediated by mitochondria.  相似文献   
9.
Stearoyl-CoA desaturase 1 (SCD1) catalyzes the synthesis of monounsaturated fatty acids (MUFA) from saturated FA. Mice with whole-body or skin-specific deletion of SCD1 are resistant to obesity. Here, we show that mice lacking SCD1 in adipose and/or liver are not protected from either genetic- (agouti; A(y)/a) or diet-induced obesity (DIO) despite a robust reduction in SCD1 MUFA products in both subcutaneous and epididymal white adipose tissue. Adipose SCD1 deletion had no effect on glucose or insulin tolerance or on hepatic triglyceride (TG) accumulation. Interestingly, lack of SCD1 from liver lowered the MUFA levels of adipose tissue and vice versa, as reflected by the changes in FA composition. Simultaneous deletion of SCD1 from liver and adipose resulted in a synergistic lowering of tissue MUFA levels, especially in the A(y)/a model in which glucose tolerance was also improved. Lastly, we found that liver and plasma TG show nearly identical genotype-dependent differences in FA composition, indicating that FA composition of plasma TG is predictive for hepatic SCD1 activity and TG FA composition. The current study suggests that SCD1 deletion from adipose and/or liver is insufficient to elicit protection from obesity, but it supports the existence of extensive lipid cross-talk between liver and adipose tissue.  相似文献   
10.
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