Electrodynamic modeling of threshold-free lasing in photonic time crystals.

An electrodynamic model is presented in this Letter to describe thresholdless lasers, utilizing the application of photonic time crystals (PTCs). By integrating the distinctive physical properties of PTCs and employing a comprehensive model based on a four-level system, the feasibility of achieving thresholdless laser operation is demonstrated. The proposed electrodynamic model comprehensively captures the intricate interplay between the electromagnetic field and the PTC medium. The model takes into account the ultrafast periodic variations in the refractive index of the PTCs, which arise from their time crystal-like behavior. Additionally, the dynamic response of the four-level system is considered, factoring in the processes of population inversion and relaxation. This Letter seeks to elucidate the underlying mechanisms that facilitate thresholdless laser operation in PTC-based systems. Through our electrodynamic modeling approach, we demonstrate that the ultrafast variations in the refractive index of PTCs give rise to a self-sustaining laser action, obviating the need for a lasing threshold. Moreover, we investigate the impact of various parameters, including pump power and modulation period, on the laser's performance and output characteristics. The developed electrodynamic model provides a comprehensive framework for comprehending and designing thresholdless lasers based on photonic time crystals. This research contributes to the advancement of thresholdless laser technology and opens up possibilities for applications in optical communications, sensing, and quantum photonics.

[Semen quality of infertile men carrying hepatitis B virus].

OBJECTIVE: To study the semen parameters of infertile men carrying hepatitis B virus (HBV) and the influence of HBV infection on semen quality. METHODS: We collected the semen samples from 782 infertility males aged 25－35 years old. According to the results of serological examinations, we divided the patients into groups A (HBsAg, HBeAb and HBcAb positive, n = 286), B (HBsAg, HBeAg and HBcAb positive, n = 230) and C (non-HBV control, n = 266), and comparatively analyzed the routine semen parameters, sperm acrosin activity, sperm DNA fragmentation index (DFI) and high DNA stainability (HDS) among the three groups of patients. RESULTS: Compared with the patients of groups B and C, those of group A showed markedly decreased sperm concentration (ï¼»88.20 ± 82.62ï¼½ and ï¼»89.29 ± 53.80ï¼½ vs ï¼»71.49 ± 60.03ï¼½ ×106/ml, P<0.05), progressively motile sperm (PMS) (ï¼»34.88 ± 15.60ï¼½% and ï¼»37.82 ± 13.63ï¼½% vs ï¼»30.70 ± 14.79ï¼½%, P<0.05), sperm motility (ï¼»45.77 ± 16.58ï¼½% and ï¼»48.16 ± 14.03ï¼½% vs ï¼»42.67 ± 17.23ï¼½%, P<0.05), sperm viability (ï¼»82.55 ± 7.55ï¼½% and ï¼»85.26 ± 6.39ï¼½% vs ï¼»81.07 ± 10.19ï¼½%, P>0.05) and morphologically normal sperm (MNS) (ï¼»6.93 ± 4.45ï¼½% and ï¼»7.27 ± 4.43ï¼½% vs ï¼»5.72 ± 3.47ï¼½%, P<0.05), with sperm concentration, PMS, sperm motility, sperm viability and MNS remarkably lower in group B than in C. Sperm acrosin activity was significantly reduced in group A in comparison with groups B and C (ï¼»57.07 ± 26.38ï¼½ vs ï¼»63.03 ± 28.75ï¼½ and ï¼»78.00 ± 33.49ï¼½ µIU/106, P<0.01), remarkably lower in group B than in C (P<0.01). The sperm DFI and HDS, however, were markedly higher in group A than in B (ï¼»14.79 ± 9.46ï¼½% vs ï¼»12.95 ± 7.29ï¼½% and ï¼»11.60 ± 5.98ï¼½%, P<0.05; ï¼»9.62 ± 6.20ï¼½% vs ï¼»8.43 ± 4.72ï¼½% and ï¼»8.41 ± 4.59ï¼½%, P<0.05), and both higher in group B than in C. CONCLUSIONS: Semen quality is lower in infertile men carrying HBV and therefore HBV infection is one of the causes of male infertility.

Nursing and observation of traditional Chinese medicine enema in treatment of gastrointestinal dysfunction in severe burn patients during infection / 中国生化药物杂志

Objective To compare the traditional Chinese medicine enema and routine enema in the period of gastrointestinal dysfunction in patients with severe burn infection the clinical effect of treatment. Methods The control group weakened symptoms on gastrointestinal peristalsis began to appear fasting, gastrointestinal decompression, anal exhaust, saline enema, parenteral nutrition, antibiotic treatment. On the basis of routine treatment in the treatment group the enema for Chinese medicine prescription. Results The curative effect in the treatment group after enema 83.3%(30/36) compared with the control group 41.70% (15/36) had significant difference (P<0.05). At the time of borborygmus, abdominal distension disappeared time, anus Exhaust time, the treatment group were (7.0±0.8)d, (3.4±0.9)d, (7.3±0.8)d, the control group were (12.6±1.8)d, (7.1±1.2)d, (13.4±1.9)d, two sets of data were compared with statistical difference (P<0.05). Conclusion The traditional Chinese medicine enema for large surface gastrointestinal dysfunction during infection deposition burn patients is rapid, safe and reliable, convenient administration, significant curative effect on gastrointestinal functions in patients with motility.

Nursing and observation of traditional Chinese medicine enema in treatment of gastrointestinal dysfunction in severe burn patients during infection / 中国生化药物杂志

Objective To compare the traditional Chinese medicine enema and routine enema in the period of gastrointestinal dysfunction in patients with severe burn infection the clinical effect of treatment. Methods The control group weakened symptoms on gastrointestinal peristalsis began to appear fasting, gastrointestinal decompression, anal exhaust, saline enema, parenteral nutrition, antibiotic treatment. On the basis of routine treatment in the treatment group the enema for Chinese medicine prescription. Results The curative effect in the treatment group after enema 83.3%(30/36) compared with the control group 41.70% (15/36) had significant difference (P<0.05). At the time of borborygmus, abdominal distension disappeared time, anus Exhaust time, the treatment group were (7.0±0.8)d, (3.4±0.9)d, (7.3±0.8)d, the control group were (12.6±1.8)d, (7.1±1.2)d, (13.4±1.9)d, two sets of data were compared with statistical difference (P<0.05). Conclusion The traditional Chinese medicine enema for large surface gastrointestinal dysfunction during infection deposition burn patients is rapid, safe and reliable, convenient administration, significant curative effect on gastrointestinal functions in patients with motility.

Clinical study of electrophysiological changes of optic nerves in early period of type 1 diabetes mellitus / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the value of pattern visual evoked potential (PVEP) and flash electroretinogram (FERG) in early diagnosis and prevention of diabetic retinopathy (DR), analyzing the correlation of early stage DR with PVEP and FERG. METHODS: Sixty patients, 30 males and 30 females, participated in observation group. Their average age was 19. 42 ± 7. 78years. The duration of DM was RESULTS: In observation group, P100 amplitude decreased and P100 latency increased, compared to those of control group ( PCONCLUSION: PVEP are sensitive to optic neuron damage; FERG is desirable to detect the lesion of Müller cells and bipolar cells. P100 amplitude by PVEP, b-wave amplitude by FERG may be the most sensitive parameter for DR at early stage.

Relationship between Staphylococcal superantigens and the dominant expression of T-cell receptor V beta gene in chronic rhinosinusitis with nasal polyp / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To analyse the relationship between superantigens produced by Staphylococcus aureus and the mRNA expression of T-cell receptor V beta region (TCR Vbeta), and to investigate the possible role of Staphylococcal superantigens in the pathogenesis of nasal polyps.</p><p><b>METHODS</b>Sinonasal mucus and polyp/mucosa tissue were obtained from patients with chronic rhinosinusitis (22 patients with bilateral nasal polyps, 15 without nasal polyps) and 12 normal subjects as comparative negative controls. Mucus specimens were assayed by enzyme-linked immunosorbent assay (ELISA) for Staphylococcal exotoxins,and analyzed for the expression of TCR Vbeta genes using the technique of reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The percentages of Staphylococcus exotoxins in nasal polyps were 54.54% (21/22) for chronic rhinosinusitis with nasal polyp (CRSwNP) subjects. There were no positive results in the CRSsNP or control groups. The expressional intensity of Vbeta3 (10.02), Vbeta14 (3.54), Vbeta15 (2.39), Vbeta17 (3.48), and Vbeta20 (2.94) was increased significantly for Staphylococcal exotoxin B (SEB) positive subjects (P < 0.05). Vbeta2 (13.8) and Vbeta6. 1-3 (6.53) were significantly highly expressed for toxic shock syndrome toxin-1 (TSTf-1) positive subjects in CRSwNP group (P < 0.05). There were no dominantly used Vbeta fragments in ELISA- negative specimens. In the group of chronic rhinosinusitis without nasal polyp (CRSsNP), most of TCR Vbeta gene subfamilies demonstrated a trend toward higher expressional levels compared with those of normal controls, although there was no statistical difference (P > 0.05).</p><p><b>CONCLUSIONS</b>There was relationship between Staphylococcal superantigens and the excursion of TCR Vbeta gene spectra in nasal polyp, and superantigens possibly play an important role in the pathogenesis of CRSwNP.</p>

Dentin matrix protein 1, a target molecule for Cbfa1 in bone, is a unique bone marker gene.

Dentin matrix protein 1 (Dmp1), a phosphoprotein highly linked to dentin formation, has also been reported to be expressed in the skeleton. However, the role of Dmp1 in skeletal tissues remains unclear. To clarify the role of Dmp1 in bone formation, we characterized the expression profile of Dmp1 in bone and cartilage and examined whether Dmp1 expression was regulated by core-binding factor a1 (Cbfa1). Studies of fetal rat calvarial (FRC) cell cultures showed that the expression of Dmp1 was associated closely with "bone nodule" formation and mineralization in vitro. In situ hybridization studies were performed to examine the spatial and temporal expression patterns of Dmp1 during development in mouse embryos from 12.5 day postcoitus (dpc) to 8 weeks postnatal; these studies showed that Dmp1 first appeared in hypertrophic cartilage cells, followed by osteoblasts, and later was expressed strongly in osteocytes. The expression profiles of Cbfa1 and Dmp1 overlapped in both cartilage and bone during development, with Cbfa1 preceding Dmp1. Examination of Dmp1 expression in Cbfa1-/- mice revealed that Dmp1 was absent in the developing bones of Cbfa1-null mice, whereas there was essentially no change in Dmp1 expression in the arrested tooth bud. Transient transfection studies showed forced expression of Dmp1 under the control of Cbfa1 and gel shift data indicated the presence of a functional osteocalcin-specific element (OSE)-2 response element in the Dmp1 proximal promoter region. However, in vitro promoter studies suggested that regulation of Dmp1 by Cbfa1 was not mediated by direct binding of Cbfa1 to this site and may be through indirect mechanisms. These studies highlight Dmp1 as a unique marker gene for osteoblastic differentiation. The close association of Dmp1 and Cbfa1 in the developing skeleton suggests that Dmp1 may play an important role in bone formation.