Constraints on Lorentz Invariance Violation from HAWC Observations of Gamma Rays above 100 TeV

Because of the high energies and long distances to the sources, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz invariance violation (LIV). Superluminal LIV enables the decay of photons at high energy. The high altitude water Cherenkov (HAWC) observatory is among the most sensitive gamma-ray instruments currently operating above 10 TeV. HAWC finds evidence of 100 TeV photon emission from at least four astrophysical sources. These observations exclude, for the strongest of the limits set, the LIV energy scale to 2.2×10^{31}  eV, over 1800 times the Planck energy and an improvement of 1 to 2 orders of magnitude over previous limits.

Multiple Galactic Sources with Emission Above 56 TeV Detected by HAWC

We present the first catalog of gamma-ray sources emitting above 56 and 100 TeV with data from the High Altitude Water Cherenkov Observatory, a wide field-of-view observatory capable of detecting gamma rays up to a few hundred TeV. Nine sources are observed above 56 TeV, all of which are likely galactic in origin. Three sources continue emitting past 100 TeV, making this the highest-energy gamma-ray source catalog to date. We report the integral flux of each of these objects. We also report spectra for three highest-energy sources and discuss the possibility that they are PeVatrons.

Salivary MMP-9 in the detection of oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour of the oral cavity. Detection of OSCC is currently based on clinical oral examination combined with histopathological evaluation of a biopsy sample. Direct contact between saliva and the oral cancer makes measurement of salivary metalloproteinase- 9 (MMP-9) an attractive alternative.

Material and Methods

In total, 30 OSCC patients and 30 healthy controls were included in this prospective study. Saliva samples from both groups were collected, centrifuged and supernatant fluid was subjected to ELISA for assessment of MMP-9. The median salivary MMP-9 values with interquartile range (IQR) of OSCC patients and the control group were statistically analysed using the Mann-Whitney U-test. The receiver operating characteristic (ROC) curve was constructed and the area under curve (AUC) was computed.

Results

The median absorbance MMP-9 value of the OSCC group was 0.186 (IQR=0.158) and that of control group was 0.156 (IQR=0.102). MMP-9 was significantly increased in the OSCC patients than in the controls by +19.2% (p=0.008). Median values in patients with recurrence and in patients with primary event were 0.233 (IQR=0.299) and 0.186 (IQR=0.134) respectively. MMP-9 was significantly increased in patients with primary event (p=0.017) compared to controls by +19.2%. No significant increase of MMP-9 level was detected when comparing patients with recurrence and healthy controls (+49.4%; p=0.074). The sensitivity value of MMP-9 was 100% whereas the specificity value was 26.7% with AUC of 0.698.

Conclusions

The present data indicates that the elevation of salivary levels of MMP-9 may be a useful adjunctive diagnostic tool for detection of OSCC. However, further studies are necessary to provide scientific and clinical validation.

Key words:Oral squamous cell carcinoma, oral cancer, saliva, salivary diagnostics, cancer detection, MMP-9, metalloproteinases.

Wearing complete dental prostheses - Effects on perioral morphology

Background

To adequately perform rehabilitation of edentulous patients by a complete removable dental prosthesis (CRDP) is from basic interest to dentists to understand the morphologic changes caused by re-establishment of a physiologic jaw relationship. Anthropometric analyses of standardized frontal view and profile photographs may help elucidate such changes.

Material and Methods

Photographs of 31 edentulous patients were compared in relaxed lip closure and after insertion of a CRDP in stable occlusion. 2232 anthropometric distances were raised. Eighteen anthropometric indices reflecting the perioral morphology and its integration in the vertical facial harmony were investigated.

Results

The intercanthal – mouth width index (p<.001), medial - lateral cutaneous upper lip height index (p=.007), lower vermilion contour index (p=.022), vermilion - total upper lip height index (p=.018), cutaneous - total upper lip height index (p=.023), upper lip - nose height index (p=.001), nose - upper face height index (p=.002), chin - mandible height index (p=.013), upper lip - mandible height index (p=.045), nose - lower face height index (p=.018), and nose - face height index (p=.029) showed significant pre- to post-treatment changes.

Conclusions

The investigated anthropometric indices presented reproducible results related to an increase in occlusal vertical dimension. Their application may be helpful in assessment, planning, and explanation of morphologic effects of CRDPs on the perioral and overall facial morphology, which may helps to improve the aesthetic outcome.

Key words:Dentures, removable dentures, anthropometry, perioral morphology.

Longterm quality of life after oncologic surgery and microvascular free flap reconstruction in patients with oral squamous cell carcinoma

Background

Quality of life (QoL) has become increasingly important in cancer treatment. It refers to the patient’s perception of the effects of the disease and therapy, and their impact on daily functioning and general feeling of well being.

Material and Methods

n this prospective study, a total of 100 patients treated at our institution, completed the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire and the specific EORTC QLQ-H&N35 module. The questionnaires were distributed to the patients between 12 and 60 months postoperatively.

Results

Global QoL score was 58.3 and mean score for functioning scale was 76.7. Fatigue (28.7 ± 26.1), followed by financial problems (27.7 ± 33.5), insomnia (26.7 ± 34.5) and pain (26.3 ± 29.9) had highest symptom score on QLQ-C30. Fatigue (r=-0.488), insomnia (r=-0.416) and pain (r =-0.448) showed highest value for significantly negative correlation to global QoL. In the H&N35 module, restriction of mouth opening (43.3 ± 38.6), dry mouth (40.7 ± 36.9), sticky saliva (37.3 ± 37.1) and eating in public (33.8 ± 31.9) were the four worst symptoms. Swallowing problem (r=-0.438), eating in public (r=-0.420) and persistent severe speech (r=-0.398) ranked as the three worst symptoms with highest value for significantly negative correlation to global QoL.

Conclusions

Longterm QoL after oncologic surgery and microvascular free flap reconstruction in patients with oral cancer is satisfactory. Measuring QoL should be considered as part of the evaluation of cancer treatment.

Key words:Longterm quality of life, oral cancer, oncologic surgery, microvascular free flap reconstruction.