Search for Dark Matter Annihilation Signals in the H.E.S.S. Inner Galaxy Survey

The central region of the Milky Way is one of the foremost locations to look for dark matter (DM) signatures. We report the first results on a search for DM particle annihilation signals using new observations from an unprecedented γ-ray survey of the Galactic Center (GC) region, i.e., the Inner Galaxy Survey, at very high energies (≳100  GeV) performed with the H.E.S.S. array of five ground-based Cherenkov telescopes. No significant γ-ray excess is found in the search region of the 2014-2020 dataset and a profile likelihood ratio analysis is carried out to set exclusion limits on the annihilation cross section ⟨σv⟩. Assuming Einasto and Navarro-Frenk-White (NFW) DM density profiles at the GC, these constraints are the strongest obtained so far in the TeV DM mass range. For the Einasto profile, the constraints reach ⟨σv⟩ values of 3.7×10^{-26}  cm^{3} s^{-1} for 1.5 TeV DM mass in the W^{+}W^{-} annihilation channel, and 1.2×10^{-26}  cm^{3} s^{-1} for 0.7 TeV DM mass in the τ^{+}τ^{-} annihilation channel. With the H.E.S.S. Inner Galaxy Survey, ground-based γ-ray observations thus probe ⟨σv⟩ values expected from thermal-relic annihilating TeV DM particles.

Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow

Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.

Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A

Previous detections of individual astrophysical sources of neutrinos are limited to the Sun and the supernova 1987A, whereas the origins of the diffuse flux of high-energy cosmic neutrinos remain unidentified. On 22 September 2017, we detected a high-energy neutrino, IceCube-170922A, with an energy of ~290 tera–electron volts. Its arrival direction was consistent with the location of a known γ-ray blazar, TXS 0506+056, observed to be in a flaring state. An extensive multiwavelength campaign followed, ranging from radio frequencies to γ-rays. These observations characterize the variability and energetics of the blazar and include the detection of TXS 0506+056 in very-high-energy γ-rays. This observation of a neutrino in spatial coincidence with a γ-ray–emitting blazar during an active phase suggests that blazars may be a source of high-energy neutrinos.

Comparison between patient-controlled analgesia and subcutaneous morphine in elderly patients after total hip replacement

BACKGROUND

The goal of this study was to evaluate the effectiveness on postoperative pain, and cognitive impact, of patient-controlled analgesia (PCA) compared with subcutaneous (s.c.) injections of morphine in elderly patients undergoing total hip replacement (THR).

METHODS

Forty patients older than 70 yr were randomly assigned to two different postoperative analgesic techniques for 48 h: i.v. PCA morphine (dose, 1 mg; lockout interval, 8 min; PCA group) or regular s.c. morphine injections (SC group). Postoperative pain was assessed at rest and when moving, using a visual analogue scale (VAS) every 4 h. A Mini Mental Status (MMS) examination was used to assess cognitive functions before surgery, at 2 h, 24 h and 48 h after surgery, and at hospital discharge. Side-effects were also recorded systematically during the first 48 h after surgery.

RESULTS

The PCA group showed significantly lower pain scores than the SC group both at rest and during mobilization. However, the clinical significance of pain scores was weak. There was no intergroup difference in postoperative MMS scores. The incidence of side-effects was similar in both groups.

CONCLUSIONS

We conclude that in healthy elderly subjects undergoing THR, the flexibility of the analgesic regimen is more important than the route of administration with regard to efficacy, adverse effects and recovery of cognitive function.

[Retrospective comparative study of extended nephrectomies by surgery and by retroperitoneal laparoscopy]

OBJECTIVE

To evaluate the results of radical retroperitoneal laparoscopic nephrectomy in terms of tolerance, morbidity and oncologic control.

MATERIAL AND METHODS

22 radical nephrectomies have been carried out by retroperitoneal laparoscopy. One surgical conversion has been necessary. This series has been retrospectively compared to 16 radical nephrectomies by open surgery.

RESULTS

Both series were comparable. Operative time was not significantly different in the two groups. Blood loss was less with laparoscopic surgery (p < 10-3). We did not see any difference in antalgic consumption during the first post-operative day and in intensive care and hospital stay. Post-operative complications were less in the laparoscopy group (p = 0.04). We observed no death or reccurrence with a mean follow-up of 8.7 months for the laparoscopy group vs 32.2 for the open group.

CONCLUSIONS

Radical retroperitoneal laparoscopic nephrectomy is a recent surgical technique which has the same oncologic standards as open surgery. Blood loss and post-operative complications are significantly reduced. Survival needs to be evaluated on long term follow-up.

[Concurrent chemotherapy and hyperfractionated radiotherapy for non-operable carcinoma of the bladder]

Two sequences of concomitant chemotherapy with 5-FU + cisplatin and hyperfractionated radiotherapy (67.2 Gy/56 fractions/38 days, two fractions of 1.2 Gy per day spaced to 6 hours) in the bladder volume were administered to 17 patients with infiltrative carcinoma of the bladder (1 pT1, 6 pT2, 8 pT3a, 2 pT3b or pT4, 8/17 N0-2). They were separated by an interval of 21 days with an intermediate bladder tumor evaluation. A complete histological response was observed in 69% (11 of 16 evaluable patients). With a mean follow-up of 21 months, the bladder preservation was stated in 8/11 (73%) of patients treated, of whom 6 with a complete tumor response, and 2 with a pTa recurrence; these results are similar to other series reported with conventional radiation therapy. No deficit in the bladder was observed in these eight patients.

[Anatomical and clinical effects of neoadjuvant hormonal treatment before radical prostatectomy]

Neoadjuvant endocrine treatment before radical prostatectomy is designed to reduce the positive margin rate and therefore the risk of recurrence. It usually consists of complete androgen blockade for 3 months, but no consensus has been reached concerning the type of blockade and the optimal duration. The main histological changes consist of glandular atrophy with pycnosis and vacuolization of tumour cells. These changes could reflect increased apoptosis. The residual tumour is usually small. PIN become rare, raising the problem of possible chemoprevention. The overall result is a markedly increased frequency of intracapsular tumours and a reduction of at least 50% of positive margins. However, some authors consider that this is simply due to a more detailed histological examination. The frequency of seminal vesicle and lymph node involvement does not appear to be modified. Endocrine therapy could act on the apoptosis-proliferation balance and also decrease the number of circulating cells. However, the intermediate results of randomized studies are contradictory. As improvement in overall survival remains the main objective, only a longer follow-up will be able to clearly determine the value or uselessness of neoadjuvant endocrine treatment before radical prostatectomy.

[Is surgery useful in kidney cancer with lymph node invasion?]

SUMMARY

lymph node involvement in renal cell carcinoma is factor of very poor prognosis. In a series of 55 node-positive patients, 33 (60%) had simultaneous renal vein or vena cava invasion and 32 (58.2%) had metastases. Gross lymph node involvement was found in 39 patients (70.9%). Patients without venous invasion or metastasis may have a prolonged survival. In this group, those with microscopic nodal involvement can be cured, as the 10 and 15-year the actuarial survival rate is 54.5% Formal lymphadenectomy might have played a role in these results. Surgery can be performed when vein invasion is present without metastasis, but the prognosis is generally poor. Survival does not seem to be influenced by surgery when metastasis is present, regardless of the vein status.