A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1-2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.

Examines how the locational choice of foreign direct investment (FDI) is influenced by regional characteristics in mainland China, such as the potential for market share extension, labour cost differences, allocative efficiency, transportation infrastructure, and research and development capability. Empirical testing is conducted by the conditional logit model using pooled cross‐section and time‐series data. Empirical findings for the 1987‐1991 period indicate that the variable for market share extension potential only affects FDI in the middle region. Surprisingly, labour cost differences do not affect the location of FDI. Interregional railroad connections are found to be positively related to the choice of location of FDI, but FDI may not necessarily locate near innovative Chinese industries.

Cutaneous sporotrichosis is a chronic granulomatous fungal infection caused by Sporothrix schenckii with worldwide distribution. Its traditional diagnosis is time-consuming and difficult to differentiate from that of a clinical sporotrichoid lesion caused by various pathogens. In this study, a nested PCR assay for the detection of S. schenckii was evaluated by using a sequence of 18S rRNA gene as a target. For the examination of specificity and sensitivity, five clinical isolates with 1 ATCC 10213 strain of S. schenckii, 10 strains of clinical common fungi, 3 strains of Mycobacterium spp., Staphylococcus aureus, and normal human skin tissue were used. The expected fragment was amplified from six S. schenckii isolates in the first round and nested PCR but not from other microorganisms and human DNA. Their sequences were 100% identical to the S. schenckii 18S rRNA gene sequence deposited in GenBank. A detection limit of 40 fg of S. schenckii DNA extract was determined with ethidium bromide staining. Serial dilution studies demonstrated that the nested PCR could detect a DNA amount of 1 CFU of S. schenckii in tissue samples. We further investigated the nested PCR assay for the detection of S. schenckii from the tail tissues of 5 experimentally infected mice and from the clinical biopsy specimens of 12 patients with sporotrichosis confirmed by culture or histochemical staining. The nested PCR assay was positive in all 5 infected mice and in 11 of the 12 clinical specimens. The high sensitivity and specificity of this nested PCR indicate that the assay can provide rapid diagnosis with sufficient accuracy to be clinically useful for patients with sporotrichosis.

DNA methylation at the 5 position of cytosine (5 mC) is an epigenetic hallmark in cancer. The 5 mC can be converted to 5-hydroxymethylcytosine (5 hmC) through a ten-eleven-translocation (TET). We investigated the impact of 5 mC, 5 hmC, TET1, and TET2 on tumorigenesis and prognosis of breast cancer. Immunohistochemistry was used to assess the levels of 5 mC, 5 hmC, TET1, and TET2 in the corresponding tumor adjacent normal (n = 309), ductal carcinoma in situ (DCIS, n = 120), and invasive ductal carcinoma (IDC, n = 309) tissues for 309 breast ductal carcinoma patients. 5 mC, 5 hmC, TET1-n, and TET2-n were significantly decreased during DCIS and IDC progression. In IDC, the decrease of 5 hmC was correlated with the cytoplasmic mislocalization of TET1 (p < 0.001) as well as poor disease-specific survival (DSS) (adjusted hazard ratio [AHR] 1.95, p = 0.003) and disease-free survival (DFS) (AHR 1.91, p = 0.006). The combined decrease of 5 mC and 5 hmC was correlated with worse DSS (AHR 2.19, p = 0.008) and DFS (AHR 1.99, p = 0.036). Stratification analysis revealed that the low level of 5 mC was associated with poor DSS (AHR 1.89, p = 0.044) and DFS (AHR 2.02, p = 0.035) for the ER/PR-positive subtype. Conversely, the low level of 5 hmC was associated with worse DSS (AHR 2.77, p = 0.002) and DFS (AHR 2.69, p = 0.006) for the ER/PR-negative subtype. The decreases of 5 mC, 5 hmC, TET1-n, and TET2-n were biomarkers of tumor development. The global reduction of 5 hmC was a poor prognostic factor for IDC, especially for ER/PR-negative subtype.

In this research, we aimed to evaluate the impact of the surface charges and morphologies of electrodes on electrochemically detecting dopamine (DA) in the presence of protein adsorption, uric acid (UA), and ascorbic acid (AA). Through the electropolymerization of functionalized 3,4-ethylenedioxythiophenes (EDOT) directly on Au electrodes, we successfully created PEDOT-coated electrodes with three different functional groups and nanostructures. Negatively charged carboxylic acid groups attracted DA while reducing the interferences of UA and AA due to electrostatic effect. We used charge-free tetra(ethylene glycol) and zwitterionic phosphocholine groups are used to evaluate the interference of protein adsorption on DA sensing because they both can effectively prevent the nonspecific adsorption of proteins. These two electrodes can avoid protein adsorption, yet proved ineffective for DA sensing: both tetra(ethylene glycol) and the phosphocholine groups are electroneutral and have minimal electrostatic interactions with DA. We also used three proteins of different isoelectric points - bovine serum albumin, lysozyme, and fibrinogen - to evaluate the influence of protein adsorption on DA detection. We found that for an electrode coated with carboxylic acid-functionalized PEDOT, the adsorption of positively charged lysozyme can promote the detection sensitivity of AA and UA, and that all protein adsorption lowers the sensitivity of DA. In contrast, nanostructures promote the detection sensitivity of all three molecules. All of our tested functionalized PEDOT-coated electrodes demonstrated good stability and functionality in buffers.

PurposeThis study aims to examine the earnings management behaviour of financially distressed listed companies in China for the period 2002‐2006.Design/methodology/approachThe present study uses discretionary accruals to serve as a proxy variable for earnings management, with the type of ultimate ownership and the type of industry to which the company belongs functioning as independent variables.FindingsThe empirical results show that the desire to avoid continued special treatment (ST) status and the risk of being de‐listed leads firms to adopt different earnings management behaviour before and after being designated as an ST firm.Research limitations/implicationsThe desire to avoid being de‐listed is as strong among managers of state‐owned companies as it is among private companies.Practical implicationsImplementing the effective regulation of corporate earnings management is therefore an issue of great importance. It is recommended that the government needs to take the degree of industry regulation into account when assessing regulations aimed at controlling earnings management.Originality/valueIn a transition economy like China, the state versus private ownership and the degree of government regulation in industry is likely to affect the earnings management of financially distressed companies. The study demonstrates that companies in less‐regulated industries tend to undertake more earnings management in the years both before and after they are designated as ST companies.

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This study uses a comprehensive sample of 763 Chinese listed companies to explore the relationship between the extent of related party transactions and operational performance. The empirical results show that when the listed company is controlled by a related party, the higher the level of related party transactions, the worse the operational performance of the listed company; this is particularly true in the case of related party transactions that involve sales, loans, guarantees and mortgages, or leases. There is thus a clear need to improve the regulation of related party transactions and the related disclosure requirements.related party transactions, corporate governance, ownership structure,