Analysis of synthetic route and case correlation of methamphetamine crystals seized by ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) and Pearson correlation coefficient method.

Analysis of impurities in illicit drugs provides key information on the manufacture and distribution of methamphetamine (MA). An analysis of 22 specific target compounds in unlawful MA products was conducted using ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). The peak area of the alkaloids was utilized as an important calculation data variable to determine the synthesis method.

Genomic insights into adaptive evolution of the species-rich cosmopolitan plant genus Rhododendron.

The species-rich cosmopolitan genus Rhododendron offers a good system for exploring the genomic mechanisms underlying adaptation to diverse habitats. Here, we report high-quality chromosomal-level genome assemblies of nine species, representing all five subgenera, different altitudinal distributions, and all flower color types of this genus. Further comprehensive genomic analyses indicate diverse adaptive strategies employed by Rhododendron, particularly adaptation to alpine and subalpine habitats by expansion/contraction of gene families involved in pathogen defense and oxidative phosphorylation, genomic convergent evolution, and gene copy-number variation.

[To estimate early postmortem interval by investigating changes of rats' gastrocnemius excitability].

Objective: To investigate the changes of excitability of rats' gastrocnemius after rats were died from mechanic asphyxia, so as to make an objective evidence for estimating of the early postmortem interval.

Methods: After rats were sacrificed by mechanic asphyxia, the reaction of rats' gastrocnemius to variable electric stimulation at different period after death were recorded by electricphysiological method.

Results: Changes in the properties of excitable tissue to electric stimulate in rats' gastrocnemius after mechanic asphyxia seems to be well correlated with the early postmortem interval and appeared a linear relation in certain period.

[Change of brainstem auditory evoked potential with different stimulating frequencies after closed diffuse brain injuries of rat].

Unlabelled: OBJECTIVE To investigate the change of peak latency (PL), interpeak latency (IPL) and peak latency ratio (PL ratio) of brainstem auditory evoked potential (BAEP) with different stimulating frequencies after closed diffuse brain injuries of rat,and provide experimental evidence for clinical diagnosis of traumatic brain injury in early stage and also for Forensic practice.

Methods: A rat model for closed diffuse brain injury was successfully constructed by hit the parietal bone with a spring-driven steel stick. The auditory brainstem response (ABR) evoked by clicking with low stimulating frequency of 10 Hz and high stimulating frequency of 50 Hz were respectively recorded at 6 h, 12 h, 2 d, 4 d after brain injury.

[Expression of Cyt C in brain of rats poisoned by tetramine].

Objective: To investigate the evidence for the judgement on legal cases of intoxication by tetramine.

Methods: Fifty rats given tetramine by lavage were sacrificed at different time after intoxication. The expression of Cyt C was detected by immunohistochemistry, and the reasults were assessed by an image analysis system.